# Scott Spark Jr 20" Custom Build



## paulm7508 (Jan 3, 2016)

Hi Guys,

New to the forum so hi to everyone!!

I bought my son a Scott Spark Jr 20" a couple of years back (too big for him then, he is now 6 and 126cm)..he was riding from an early age and wanted to see where it leads. This has naturally progressed to doing a custom build for him so I thought I would share some pics (these threads have been an inspiration, so giving something back!!) and ask for any feedback or advice on the build and what is yet to come.

Here is a picture of the bike stock, (if you needed any reminding!!);








The list of parts I have added so far:

Bars - Raceface Ride XC (hanging around in parts bin, 30mm cut of either side to shorten)
Stem - Funn Crossfire 2012
Front Brake - Avid Elixir R (180mm disc, what I had in stock!!!)
Rear Brake - Promax Click P1 rim brake
Wheels - Shimano XT Hubs, Alienation Deviant rim (front) and Alienation Delinquent rim (rear)















The next mods will be to sort out the cranks (looking for 145mm length, suggestions would be appreciated!), looking to run a 1x9.. will be utilising an old SLX rear derailleur with short cage conversion. I have some old XT shifters in the shed as well so one of these will be used. The suspension also needs some attention so looking to go with the 24" Spinner Grind OS Air fork, (within budget, otherwise would love to get an 20" MRP Rustler) and a Kind Shocks KS A5-RR1 shock to sort out the rear.

I will keep uploading pics as the build progresses. Oli has his first race(s) coming up this year so will add in some film of this also, (I have some film now of him doing some jumps but issues uploading them to the computer - will put these up soon!!!)

As I said, any feedback would be appreciated, thanks!


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## FREAKAH (Sep 11, 2013)

Very nice build so far!!

That's the bike I wanted to get for my son when he was younger. We eventually got a Hotrock 20 that we eventually sold earlier this year so he could get a 24" bike.


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## paulm7508 (Jan 3, 2016)

Thanks, definitely a work in progress but he still has a good year left on the bike and a younger brother so worth the effort! What 24" bike have you gone with?


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## paulm7508 (Jan 3, 2016)

Well I did say I would put up a video. Only a short one but working on a decent, longer vid that shows off his skills


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## Will Fisher (May 12, 2015)

@paulmm7508, looking good! I've been working on my son's Spark along and along and he loves it. Here are a few pictures. I swapped out the bars, seat post and stem for carbon from Ali Express, Redline 145mm cranks and BB from Dan's Comp, a Suntour Lo Air 24 fork and disc front wheel from a Hot Rock Pro 20, KS A5-RR1 shock from Ali Express, and, to go 1x9, I am going to trade out the back wheel with a Sun Envy Light rim laced to an XT hub, XT derailleur 12-36 cassette and XTR shifter. Doing it bit by bit it hasn't been too expensive and I already had some in the parts bin. He's the oldest of three so I foresee us getting a lot of use out of this bike.
Before







Current Set Up


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## paulm7508 (Jan 3, 2016)

That looks superb!! How have you and your son found the KS A5-RR1 shock? Just ordered one up yesterday...


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## paulm7508 (Jan 3, 2016)

What weight is that currently running at Will?


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## Will Fisher (May 12, 2015)

Paul, the shock is fine. Pretty basic but definitely better, and a lot lighter, than the pogo stick spring that came on it. Weight-wise we're at about 23 lbs. $35-40 for a carbon set from China saved almost 2 lbs over the stock steel. All those stickers serve the dual purpose of a) kids love stickers and b) keeps it from getting all scratched/banged up.


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## Will Fisher (May 12, 2015)

Out of everything I've done to it, the biggest hit was this cap: Sugar Skull w/ Bolt Bicycle Headset Cap by KustomCaps | KustomCaps


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## paulm7508 (Jan 3, 2016)

Just showed my son that cap...his exact words were "cool...i want one of those on my Scott!!" What chain guide are you running?


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## Will Fisher (May 12, 2015)

Paul, not sure what type of chaing guard it is as it came off of a Hot Rock Pro 20. But the chainring is a 34T MCS 110bcd from Dan Comp. I am pretty sure that Wolf Tooth makes a narrow wide 34 that'll fit these cranks. 

Last time we went riding he couldn't get up the steep hills with the 34/28, so hopefully this 12-36 will help. He's tried trigger shifters, as opposed to the grip shifters, and they seem easier for him to use, so I'll throw on my old XTR one once I get his new wheel built.


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## Will Fisher (May 12, 2015)

Paul, also, just to confirm,an XT M756A 135mm hub will fit fine on the Spark?


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## paulm7508 (Jan 3, 2016)

Thats good news..just a case of finding the right crankset now. Was looking at this with interest:
GT Speed Series Cranks Alum Black 2014 [GT Speed] - $129.99 : ACEBMX, BMX Bikes, BMX Frames, BMX Parts, BMX Racing, BMX Cranks, BMX Wheels, Order BMX Bicycles, Freestyle Bikes, BMX Online Sales
I cant fit the new rear wheel he had built until i sort the gearing (cassette fitting different on new hub) so looking to do a bulk buy at the end of the month (crankset, cassette, chain, chain guide, etc.) going to have a nice bit to build with the shock on its way as well!!


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## Will Fisher (May 12, 2015)

Those cranks look good. Keep posting pictures as the build progresses!


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## FREAKAH (Sep 11, 2013)

Call and make sure ACE has the correct item in stock. Heard a lot of stories where they would send something else if the item that was ordered was not in stock.


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## paulm7508 (Jan 3, 2016)

Cheers for the heads up FREAKAH. Buying from the UK as well so last thing i need!


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## Will Fisher (May 12, 2015)

I threw on the shifter and derailleur tonight and got it all set up using my daughters back wheel from her Hot Rock, hence the purple tire. We'll hopefully have the other one in a few weeks.


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## OutdoorMan01 (Dec 19, 2015)

Nice bike, BRAVO !!!

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## RMCDan (Feb 28, 2008)

Will - How do you like that fork?


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## paulm7508 (Jan 3, 2016)

So the bits i need to do a short cage coversion on the SLX derailleur aren't going to come after all...thinking of going with a 10 speed shimano zee (have zee kit on my Identity mr hyde, great stuff). Shopping around for a chain guide, obv no iscg mounts but any idea what the fitment is? After a top and bottom...


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## RMCDan (Feb 28, 2008)

paulm7508 said:


> So the bits i need to do a short cage coversion on the SLX derailleur aren't going to come after all...thinking of going with a 10 speed shimano zee (have zee kit on my Identity mr hyde, great stuff). Shopping around for a chain guide, obv no iscg mounts but any idea what the fitment is? After a top and bottom...


Get a N/W chainring to go with the Zee and you'll have no need for a chainguide.


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## paulm7508 (Jan 3, 2016)

Part of the appeal of the chainguide is the protection it offers Oli from the chainring as well, (yet to find a decent looking bashguard but may go this route)....have to admit wanting top and bottom CG is also me being a tart!!!😊


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## Will Fisher (May 12, 2015)

So far we've been very pleased with the fork. Random question but has anyone ever thrown a 24" front wheel on? Little man is way too small for that now but just curious. 

Also, he can shift MUCH easier with the trigger shifter vs the grip.


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## Will Fisher (May 12, 2015)

Final build (for now)










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## Erock503 (Oct 20, 2014)

Will Fisher said:


> So far we've been very pleased with the fork. Random question but has anyone ever thrown a 24" front wheel on? Little man is way too small for that now but just curious.
> 
> Also, he can shift MUCH easier with the trigger shifter vs the grip.


Did you find it altered the handling a lot with the bigger 24" a2c? I have a 24" fork I bought for my sons 20" bike, but I'm hesitant to add that much height to it after seeing it in person.


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## Will Fisher (May 12, 2015)

@erock503 we've been pleased and haven't noticed a handling difference and having the adjustable air fork definitely improved his riding.


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## Erock503 (Oct 20, 2014)

Will Fisher said:


> @erock503 we've been pleased and haven't noticed a handling difference and having the adjustable air fork definitely improved his riding.


Thanks man. Btw, forgot to mention it, but great job on the bike, my sons would be envious!


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## Will Fisher (May 12, 2015)

Thanks erock! This is for my son who's the oldest of three, so we'll get a lot of use out of it over the next five or so years.


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## paulm7508 (Jan 3, 2016)

So just bought some SRAM S600 cranks for the Scott, ready for shortening. Did look at quite a few options but few in a 104 bcd which i was after. Can anyone give me the correct bb length for a splined drive? Once shortening done (nexf week hopefully) i have an SLX cassette and Zee derailleur & shifter to fit. Rear shock is on its way then its just waitong for the Spinner fork to be back in stock in March! More pics soon!


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## paulm7508 (Jan 3, 2016)

So the SRAM S600 cranks are now shortened, look fantastic at 135mm. I have also had the KS A5-RR1 shock through the post this morning so that will be going on today. First thoughts are it looks like a decent unit, (obviously not Fox or anything!) but as its the RR1 version the fitting may be interesting, making sure the negative-side valve does not interrupt the travel when in the frame....how has everyone else found this?

BTW i was thinking of perhaps getting a load of these cranks and selling them shortened so if anyone is interested let me know.


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## Will Fisher (May 12, 2015)

Paul, I put it in upside down (see pics in thread)


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## Will Fisher (May 12, 2015)

Cranks look great, BTW!


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## paulm7508 (Jan 3, 2016)

Cheers Will.
Will, had a go at fitting it in several ways but noticed that when fitting it upside down with the negative chamber valve on the top tube mount the main chamber valve was hitting the linkage and limiting the travel, (although this is the only layout that allows access to both valves). In the end I swapped the linkage over and fitted it negative valve on the linkage side. The valve does contact the linkage mounting, (see pic) but once Oli's is on the bike it is clear and allows for full travel, downside is you have to remove the shock to set the negative pressure.


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## Will Fisher (May 12, 2015)

Paul, I guess I actually have it upside down and backwards; the negative chamber is to the front. But I can easily access both valves. Let me know what psi you're using in each after you get a chance to play around with it.


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## Andrew Reznick (Apr 15, 2014)

Hi guys - nice mods and good work. My twin boys rode the exact blue Scott pictured at the start of this thread for two years, ages 6-7. We have done TONS of biking, and they are now 8 year old expert riders. For their 8th birthday (last June), I decided to buy them Lil Shredders with 20 inch wheels. This was a painful decision (financially) especially realizing that they will only get 2 years use out of them. Anyway, here is what I have learned (some of this is obviously opinion): WEIGHT is not terribly important, but GEOMETRY and FUNCTION are very important. Suspension is also important. Bearing this in mind, here is my advice:
1) Cranks - the stock cranks on the Scott are 140 mm. The ideal length would be 135 mm for a 6-8 year old. Therefore, I recommend keeping the original cranks. Changing them to save a few ounces is a waste of time and money. Going up to 145 mm cranks would be a step in the wrong direction - even if the cranks are "better." 
2) Gearing - the stock 2x6 works relatively well except that it does not have any gears easy enough for a 6-8 year old to climb. EASY gears are important! EASY gears allow for climbing way more than a 2-3 pound lighter bike! The easy front chain ring has 34 teeth, and the hard ring has more. Compare to the Shredder where the ONLY front chain ring has 30 teeth (although Shredder uses a 11-36 rear cassette which gives more hard gears than the 14-28 range of the Scott). I recommend changing the front of the Scott to a 2x6 with a 30 tooth easy gear. My boys can climb better on their shredders, but they miss the large chain ring on their Scotts. I'm thinking about changing their front ring to 34 teeth this summer since they will be nine years old and 4' 4" (we are not a very tall family).
3) Rear shock - the stock coil shock works fairly well. It moves appropriately with a 40-60 lb rider. After several years of use, it never developed "sticktion". I would keep it since I don't think you will make a different shock work much better on the bike.
4) FORK - this is the biggest problem on the Scott spark, and very important in terms of absorbing bumps which derail kids and cause crashes. Way too stiff, not enough travel, terrible sticktion.... That said, my boys shredded the stock fork for two years. It is critical to add a few drops of chain grease to the stanchions every single ride. 
ADVICE: The 20 inch wheel Lil Shredder fork is awesome (procured directly from Taiwan by Lil Shredder, not available on any other bike). 100 mm travel with a buttery air spring, adjustable to your kids exact weight, and with rebound adjust. You can probably buy one for $400 from Lil Shredder (Brian from Lil Shredder offered to sell me forks although maybe because we are friends. He is super nice and probably would sell you one too if you contact him). Next, I would recommend the Sun Tour air fork designed for a 24 inch bike. It has 60 mm of air-sprung travel which works well according to reviews. Specialized puts this on their "Hotrock 20 Pro", so I think it would be fine to put on a 20 inch bike. It is also lighter than the stock fork, and I think you can get this from Sun Tour for less than $200.
5) Geometry - kids want the same thing we adults want in "all mountain" geometry. That is, a "slack" 67 degree head tube angle, short chain stays, low stand over. Right? Well, the Scott Spark Jr 20 was designed in 2004 as a cross country bike - and the geometry was never changed after 2004. It has a steep 70 degree head tube angle and relatively long chain stays. There is essentially nothing you can do about this. However, using the fork designed for a 24 inch bike (the Sun Tour) will increase the head tube angle somewhat which should be an improvement. So would the 20 inch Lil Shredder Fork which is longer than the stock fork.
6) Shifters and derailleurs: the important thing is that kiddos can shift them! My kids could not turn the twist shifters, and the stock plastic derailleur was so crappy that it could never stay in tune. I changed the rear shifter and rear derailleur to Shimano Acera (7 speeds works fine with 6 gear cassette, made of metal, shifts accurately). Again, this is about function, not weight. XT would be even better because they require less thumb pressure to shift, but this necessitates a new cassette, new hub, etc. 
7) Disc brakes - very important for kids due to hand fatigue. However, the rim brakes are okay as long as you keep them well tuned and replace the pads each season. We did lots of downhills on them. Looks like you have a front disc already. You may be able to get a rear disc too by getting a disc adapter for the frame from "A2Z". Not sure if the A2Z rear disc adapter would fit a Scott spark, but probably would. But then you would need a new rear hub, wheel, etc which adds money.

Bottom line - the Scott Spark works well out of the box except for the shifter and rear derailleur. My kids had a blast on them and grew their skills tremendously. Certainly would be a great bike for the casual riding family. If you are more of a "hard core" riding family as we are, and you go down the road of getting a new fork, new drive train, new bars, new wheel set, new cranks, and disc brakes - you will have spent a lot of time and money on mods - and you will have a bike that is still not nearly as good as a Lil Shredder. I would just buy a little shredder and hope to get back 60% of the price when you sell it. I wish I had done this sooner so my kids would have gotten more use out of them.

Another extremely nice and price-effective alternative would be the Commencal Supreme 20. Again, it has sweet geometry, very functional shocks, fork, and discs for about 1/2 the price of a Shredder. It only needs a rear derailleur, cassette, and shifter added - which you already have in the garage or can buy on sale on-line. The rear hub is already compatible with a 1x9 or 1x10 cassette, so you do not need to rebuild the rear wheel. Again, I don't think you could build up a Scott to be as nice as the Commencal because of the differences in the frame geometry and suspension. Also, I would not change anything on a Commencal to save weight. As soon as you start adding money to modify a Commencal, you might as well buy a Shredder.

Here is a video of my boys riding in case you're interested, age 8 on Shredders: 





Here they are on their Scott Sparks, age 6. This is less impressive mostly because they are younger, not because of the different bikes.


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## paulm7508 (Jan 3, 2016)

Hi Andrew,

Thanks for the advice and the video's look great. 
I bought the Scott for Oli when he was 4 and not sure if he was going to get into riding. Since then, (he is nearly 7), I can see that it is something that he is really getting into and so the bike has started to evolve with him. Believe me I would love to get him a Lil Shredder but he is not too far from moving up to a 24" bike and I can't justify the spend for the limited time he will be using it. 
As with any project things have gathered pace over time - originally i wanted better brakes to help with the faster/steeper trails he was riding so wanted to go disc, this meant a new front wheel, then new rear wheel to match, new drive train, etc. Something that I have noticed very much on the stock bike is the poor quality of the bearings so would have wanted those changed anyway. With the rear shock I was watching him go down some local trails, (quite steep with lots of small doubles) and the rear shock was acting like a pogo stick and throwing him off line, (if not off completely) so, although we have only been on two rides since fitting it, the new shock has been excellent in preventing this. I agree that the front forks need to swapped out for a better option and was looking at going down the 24" fork route;

GRIND OS AIR 24" / GRIND OS AIR 20" Bike Forks - Spinner-USA Supplier

(If anyone has the axle to crown length it would be appreciated!!)

I've just spent some time on his bike tonight


























It will be going into the LBS in the next couple of days to have the cranks fitted, (Moving house Friday, required tools are nowhere to be found, plus trying to strike up a relationship for future sponsorship perhaps?!) so will be finished off then until the forks arrive next month.

I've actually drawn up some custom suspension linkages over the weekend that, if i have worked it out correctly, should increase the rear travel from 60mm to 73-75mm(ish). Will have them made up in a few weeks and put up some pictures.

Getting back to the original point Andrew, we have also used modding this bike as a means of making sure that Oli works hard at school, behaves himself, etc. and it seems to have worked well that way, so although buying something great out-of-the-box would be fantastic it has been a mini adventure modding the Scott with him and seeing him improve with the bike. The financial pain comes when we look to get him a Propain Yuma in 12-18 months!!!


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## paulm7508 (Jan 3, 2016)

Will Fisher said:


> Paul, I guess I actually have it upside down and backwards; the negative chamber is to the front. But I can easily access both valves. Let me know what psi you're using in each after you get a chance to play around with it.
> 
> View attachment 1048416


Will, taken the bike out a couple of times with the KS A5 fitted. at the minute we have the main chamber pressure at 90 psi and the negative at 55psi. I haven't weighed Oli in a while so can't tell you how this relates. What are you running your son's at?


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## paulm7508 (Jan 3, 2016)

Saw this build thread last night - Great Scott Spark Jr build!!

Build report - custom Scott Spark 20 Junior « Singletrack Forum


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## Will Fisher (May 12, 2015)

Paul, I have it at like 60/40 but plan on taking the pump with us next time and playing around with it.

I know I said I was done, but my daughter needed her wheel back so I got some Deviant's laced to an XT hub paired with a 12-38 cassette. I got new pedals for my bike and so threw my old red CB 5050s on. The red, blue and black combo on the rear wheel is rad, but I'm going to avoid the temptation of getting a matching front.










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## Steve-XtC (Feb 7, 2016)

paulm7508 said:


> So the SRAM S600 cranks are now shortened, look fantastic at 135mm. I have also had the KS A5-RR1 shock through the post this morning so that will be going on today. First thoughts are it looks like a decent unit, (obviously not Fox or anything!) but as its the RR1 version the fitting may be interesting, making sure the negative-side valve does not interrupt the travel when in the frame....how has everyone else found this?
> 
> BTW i was thinking of perhaps getting a load of these cranks and selling them shortened so if anyone is interested let me know.


Hmmmm.... it pays to read first, spend later!

I just laid out for the taps and a tap wrench! 
DUH...... (I'm in Woking so would have really made sense to pay someone)

RE: 24 inchers ...
You may have made a rod for your own back on the 20 incher ?? 

£250 for Frame and Shocks

CANNONDALE RACE GIRLS 24" 2014 :: £249.99 :: Kids Bikes :: 24" Wheel (9 to 11 yrs) :: Pauls Cycles
Significantly comes with RST F1rst Air shocks.

Frame seems fairly light... I didn't actually weigh it though. 
Its got mountings for disc's on the frame .... 
RIMS are ALEX Z1000 (not bad)
Hubs are without disc mounts 

I'm just sticking a 1x10 on for now. Got a crap wheel for £40 while I find something better that takes a cassette. May add disc brakes later.

Forks really perform well. We took it out on single track and I tuned the forks while we were out.


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## paulm7508 (Jan 3, 2016)

Will Fisher said:


> Paul, I have it at like 60/40 but plan on taking the pump with us next time and playing around with it.
> 
> I know I said I was done, but my daughter needed her wheel back so I got some Deviant's laced to an XT hub paired with a 12-38 cassette. I got new pedals for my bike and so threw my old red CB 5050s on. The red, blue and black combo on the rear wheel is rad, but I'm going to avoid the temptation of getting a matching front.
> 
> ...


Don't avoid the temptation will, matching wheels look awesome!!! ?


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## kheaton (Feb 20, 2015)

"(If anyone has the axle to crown length it would be appreciated!!)"


432mm in 80mm travel setting 

452mm in 100mm travel

This is from the measured drawings for the 24" OS air

Ken


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## Will Fisher (May 12, 2015)

And the final touch! A custom Wyoming State Flag headset cap. Got them made for my company and my son snagged one for his bike









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## Warren569 (Mar 4, 2016)

*Spark JR 20 custom ideas*

Paulm7508 - thanks for posting up the build thread, same goes to Will and Andrew. I bought my 6yr old a Orbea MX20 trail hardtail last April, as it had a really nice hydroformed frame and then added some custom disk wheels, Spinner Grind 20 air forks and other bits of bling. I had some old Mono mini disk brakes and a Ti seatpost in the shed which were added too. The bike now weighs the same as a Isla Benin 20 but with a much higher spec (will add pics when I can work out how to reduce their file size). However, having seen the Scott FR20 builds, I am now contemplating doing my own version and have already sourced a good second hand bike as a basis which should arrive in a couple of weeks.
Plan:
a) Use existing parts bought for Orbea e.g. Shimano/Halo wheelset, Ti post, Hope Mono Mini brakes, carbon bar, short stem, Aest Ti pedals, Ti skewers, Ti seat clamp 
b) Use other bits I have sat in parts bin - Answer 135mm cranks, Answer Ti bottom bracket (both from sons bmx race bike), Hope Doctor rear disc adaptor, possible use of KS dropper post (27.2 diameter but lot of added weight)
c) Some new bits - A5 RR1 shock, new linkage bearings 
d) Custom bits - file out cable guides and powder coat frame

Questions:
1) If I look on Alibaba, the KS RR1 is listed as no longer available? Who did you order from as I've written to KS directly but no response as yet?
2) Can you share drawings of new linkages, or even better consider having a batch made so we can have some too. To that end, has anyone tried offset shock bushes, which would slacken head angle and lower BB? 
3) Has anyone tried ghetto tubless e.g. using a 16" tube cut in half with sealant?
4) Lastly, what is the biggest volume off-road tyres available in 20". They may work better than trying to eek out a few extra mm of travel?

Many Thanks,
Warren


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## dietz31684 (Mar 30, 2010)

Will Fisher said:


> And the final touch! A custom Wyoming State Flag headset cap. Got them made for my company and my son snagged one for his bike
> 
> 
> 
> ...


Great cap, but that's a buffalo not a seal.

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## Will Fisher (May 12, 2015)

Warren569 said:


> Paulm7508 -
> 
> Questions:
> 1) If I look on Alibaba, the KS RR1 is listed as no longer available? Who did you order from as I've written to KS directly but no response as yet?


Taiwan Kindshock A5 RR1 Rear Shocks for MTB Bicycle Rear Shock Bike Mountain Bicycle Rear Shock 150mm A5 RR1-in Bicycle Frame from Sports & Entertainment on Aliexpress.com | Alibaba Group

This is the one we got. Took two or three weeks to arrive to NC.


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## Warren569 (Mar 4, 2016)

Will Fisher said:


> Taiwan Kindshock A5 RR1 Rear Shocks for MTB Bicycle Rear Shock Bike Mountain Bicycle Rear Shock 150mm A5 RR1-in Bicycle Frame from Sports & Entertainment on Aliexpress.com | Alibaba Group
> 
> This is the one we got. Took two or three weeks to arrive to NC.


Thanks for the link, unfortunately that upplier said it was no longer available. I have sourced another supplier, so will wait and see how long it will take to send. I should be getting the bike delivered tomorrow, so the work to strip it down and get it off to powder coating begins.


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## Will Fisher (May 12, 2015)

I know I said I was done but I found an older SID Carbon fork locally for a great price and couldn't resist. The A2C is only about 20mm more than the 24" Suntour fork we were using so I figured we'd give it a try. The SID is 500+ grams lighter. We'll give it a go this weekend and see how it does. Worst case scenario we'll save it until he moves up to a 24 or I'll throw it on my hardtail.

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## Warren569 (Mar 4, 2016)

*Build Update*

I've managed to complete (almost) my own JR20, so thanks to all who have contributed on this thread for the inspiration and help. Will try to document what worked / what didn't work to help others who might try the same.

Started out with this, a little tired second hand Spark.


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## Warren569 (Mar 4, 2016)

*Build Update part 2*

After initial strip down, I realised the frame is totally over-built and ready for anything a 5-8yr old can throw at it. Then it was time to grind off all of the cable guides(!), with plan to use stick-on ones later and send frame off to powder coat in sons favorite yellow. Whilst this was away, I ordered a replacement shock (KS RS5) as the original had zero damping. Then I found a 5.5" e2e Fox Float L on Fleebay and my plans changed!!

With the frame back from powder coat, I reassembled and found the frame needed modifications to fit the new shock, which is longer than the original. This required me to (gulp!) cut off the shock mounts on front and drill new holes for the front mount. I also modified the shock linkages to allow more travel by carefully grinding the back edge and also adding offset bushes to get a slacker head angle (note: there wasn't much room to do this when drilling the new front shock mount, as I needed to make sure I didn't have any clearance issues with the top tube)









First mistake: Don't send frame to powder coat until you've built bike up to make sure everything fits!


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## Warren569 (Mar 4, 2016)

*Build Update part 3*

....contd

Now I had a working shock and linkage, time for the build. My son chose the decal colour scheme and I switched the parts I already had over from his hard tail, these included:

Grind Air forks - I had to strip and rebuild these, which made a world of difference as there was a lot of 'debris' mixed in with the grease. I also had some softer springs from another project, which worked a treat on the air spring side. Lastly, I re-used an old Chris King headset crown race that slackens head angle another degree
Gears - Zee short mech and 10 speed shifter was used with an almost new XT cassette (all from my parts bin)
Disc wheels - custom built using Halo BMX rims and Shimano hubs
Brakes - an old set of Hope Mono mini's (160mm front, 140mm rear)









Build as was...next for the cranks and final set-up...


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## Warren569 (Mar 4, 2016)

*Build update part 4*

Cont.d....Last bit (promise)

I had some concerns about the shock i.e. it was overdampred for my 25kg 6 yr old. I fixed this by removing the air sleave and literally letting out a little bit of oil/nitrogen from the damper, bit by bit until I got the right level i.e. best guess!

I added some One One Knuckleball bars cut down from 780mm! and a On-One stem. I KMC X10SL was added along with a cable (Clarkes I think).

The Crank and BB are Answer, from last years race BMX - the Answer Slider BB is Ti and allows you to move the crank within the BB to get a better chain alignment. 








I also fitted an old Blackspire chain device to help keep the chain on. I only had 5 of the stick-on cable guides, so had to be 'creative' with cable and brake hose routing but they work (just). Front brake hose is a bit short as they were used on narrower bars previously.

Finishing off, I used AEST headset, Ti pedals, Ti Skewers and Lightweight seat post clamp. I also cut @3" off the original seat-post as it is way too long and is just carrying extra weight.

Finished bike:

































Hope you like it. It was built for my boys 7th birthday and although a week late, he absolutely loves it. He's hit jumps in the back garden so far but will be doing a DH race on 1st May on it and trips planned to Wales and France over the summer!!


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## paulm7508 (Jan 3, 2016)

Hi All!































Sorry it's been a while since I last posted an update on Oli's Scott but I have had a lot going on recently...this is not to say that we haven't been progressing! I finally got around to putting the drivetrain together which meant we could use the rear wheel we had made for us by the LBS, (The Riders Guild in Chichester, if you ever get the chance to go in there do - great bunch of guys and do some fantastic work). the only bits we have now to finish it off are the spinner Grind OS air fork, (been told the distributor will have these this week), new headset, (Cane Creek - sat in my garage) and for me to pull my finger out and get these custom suspension linkages made, (all designed just need to get made up and anodised - what do we think of candy red to match the rear brake?!)


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## paulm7508 (Jan 3, 2016)

Warren569, are these the 20" Spinners or the 24"s?


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## Warren569 (Mar 4, 2016)

paulm7508 said:


> Warren569, are these the 20" Spinners or the 24"s?


I used the 20" Spinners. Ordered from a distributor in Poland, great service and quality product for the price. Still too hard out of the box though, I had to service and put a lighter spring in them


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## paulm7508 (Jan 3, 2016)

Warren569 said:


> I used the 20" Spinners. Ordered from a distributor in Poland, great service and quality product for the price. Still too hard out of the box though, I had to service and put a lighter spring in them


Where did you source the spring from Warren?


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## paulm7508 (Jan 3, 2016)

Will Fisher said:


> I know I said I was done but I found an older SID Carbon fork locally for a great price and couldn't resist. The A2C is only about 20mm more than the 24" Suntour fork we were using so I figured we'd give it a try. The SID is 500+ grams lighter. We'll give it a go this weekend and see how it does. Worst case scenario we'll save it until he moves up to a 24 or I'll throw it on my hardtail.
> 
> Sent from my iPhone using Tapatalk


How have you found this fork Will? what is the axle to crown length on that?


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## paulm7508 (Jan 3, 2016)

Link to a quick video I put together for Oli...

New forks are now on and looking sweet so I will upload a couple of pictures tonight.

Enjoy!!


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## paulm7508 (Jan 3, 2016)

*Final Build*

Here we go.....Forks on and already a big improvement. Oli has said he feels much more comfortable on the bike and seems to be much more confident on the down stuff!!


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## Kingfisher2011 (Nov 1, 2011)

Gentlemen, these bikes are just sick. Thank you for validating the fact that I spoil my children... albeit not as bad as you guys... yet.  It also gets my ADD spinning again over the Spinner fork. I think the Felt 20" I bought for my oldest is a great little bike for him, but the Suntour fork has got to go if he gets serious, and for the price, the Spinner is a sacrifice I can make.

To revisit the question someone else asked, where'd you snag the lighter spring and how bad was it to get it installed?


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## Steve-XtC (Feb 7, 2016)

We had no problems with the 40t with roots or rock though I had thought we might. We did pick up the odd loose stick that would have perhaps trashed a low end rear mech But the (used) XT 780 has chewed them rather than the inverse 

Main issues were stiff shifting which I solved by a good quality cable ... 


Sent from my iPhone using Tapatalk


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## Will Fisher (May 12, 2015)

We went out to the Tetons for a month and little man has been riding with me a bunch. Here's a slow mo video of him practicing creek crossings, him suited up to ride downhill at JH Mtn Resort and one of him out on a trail on the Pass. Bike worked liked a charm and he's now super stoked on riding!


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## Kingfisher2011 (Nov 1, 2011)

Wish we had scenery like that around here with more open singletrack. Looks awesome!


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## rdblatch (Jun 6, 2008)

This is an awesome thread. Thank you all.

My son has been riding with a friend at Trestle Bike Park at Winter Park, Colorado. He's been borrowing a Commencal 20 Supreme (which is awesome, btw), but now it's time for his own bike. A friend of a friend was selling an already upgraded Scott Spark 20 for a great entry level price, so I jumped on it.

It already has hydraulic disc brakes, custom wheels, upgraded shifters and bars. But the fork and shock are stock. I've been scouring all of these threads and I'm only getting more confused as to what is 'best'.

I'd like to upgrade both the fork and shock (and not spend so much that I should just buy a Commencal). These seem to be my best options, I'm hoping for your expert opinions.

*Shock:*
1) Kind Shock A5-RR1 ($75). 
- Is this easy to install? 
- Do I need anything custom? 
- How much better than the stock does this work?

2a) Risse Racing Custom Genesis ($198)

2b) Risse Racing Custom Astro-5 ($298)
- Are either of these any good? They look pretty high quality.
- Is the Astro-5 worth $100 more?

3) X-fusion - but I can't seem to find a 125mm version any more.

4) Others to consider or recommended?

*Fork*

1) Spinner Grind Air - I can't seem to find a price. My son has this on his Spawn Savage and it seems to be OK. No idea how much they cost or where to get them.

2) Spinner 300 Air - Same as above. Seems like a slightly beefier shock. I suspect more expensive too.

3) White Brothers - too expensive

4) Lil Shredder - $400 per this thread (if I could get it for that, it's probably still a bit steep.)

5) Suntour? 24" or 20"? Better than Spinner?

6) RockShox SID (are these available anywhere)? Recommended?

Thanks everyone!!


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## Will Fisher (May 12, 2015)

RD, some people may disagree with me throwing a 26" fork on my son's Spark but it's been great so far. We did have the Suntour XC Lo Air on it but I found a deal on the carbon SID and saved like 800 grams (1200 vs 2,000 grams) and have it sprung perfectly for his weight. The video I posted above is grainy but you can see the fork soaking up the bumps as he hit the rocks in the creek. It also slacked out the head angle a bit so he's less like to endo on anything steep. And it was only about an inch longer than the Suntour we had on there. When you hold the two forks you can tell a world of difference; the Suntour feels like a brick compared to the carbon SID.

The A5-RR1 seems to work pretty well though it doesn't have much travel; like maybe an inch. And it's probably a half pound lighter than the stock steel spring. I'd say give it a try. Kids don't have creaky old knees like us so probably not super important. And the A5 took about 30 seconds to install. 

Lastly, we left on the stock rear brake and it's been fine. But post some pics of the bike when you have a chance.


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## rdblatch (Jun 6, 2008)

Thanks Will.

Besides the weight difference, what do you think of the A5-RR1 vs. the stock shock? Is it the same amount of travel? Seems like the stock is getting around 2 inches or so. The Risse Racing folks told me the Genesis would get about 2.5inches.

Thanks again.


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## Erock503 (Oct 20, 2014)

Will Fisher said:


> RD, some people may disagree with me throwing a 26" fork on my son's Spark but it's been great so far. We did have the Suntour XC Lo Air on it but I found a deal on the carbon SID and saved like 800 grams (1200 vs 2,000 grams) and have it sprung perfectly for his weight. The video I posted above is grainy but you can see the fork soaking up the bumps as he hit the rocks in the creek. It also slacked out the head angle a bit so he's less like to endo on anything steep. And it was only about an inch longer than the Suntour we had on there. When you hold the two forks you can tell a world of difference; the Suntour feels like a brick compared to the carbon SID.
> 
> The A5-RR1 seems to work pretty well though it doesn't have much travel; like maybe an inch. And it's probably a half pound lighter than the stock steel spring. I'd say give it a try. Kids don't have creaky old knees like us so probably not super important. And the A5 took about 30 seconds to install.
> 
> Lastly, we left on the stock rear brake and it's been fine. But post some pics of the bike when you have a chance.


The only thing I would caution about adding too much to the AC ratio, is putting stress on parts of the frame that weren't designed for it because of the angles. Most frame makers will void the warranty if a bike is run with a longer fork than the frame was designed for. Maybe it doesn't matter as much with a kids weight, but you normally want to stay within the tolerances of the frame. Not disagreeing with you, just playing devils advocate.

btw, these bikes look awesome!


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## Andrew Reznick (Apr 15, 2014)

RDblatchrblatch -=20

OVERALL: Sweet that you got a Scott with custom wheels and discs. =
Discs are very important for little dudes and the biggest reason why I =
decided my boys needed new bikes. You may consider having your guy ride =
it as-is and see how it goes. Remember to add a drop of oil to the fork =
stanchions every ride. If he likes it, maybe don't do anything. =
If he immediately notices that the Commencal was way better, maybe =
consider buying a Commencal - especially if you will be doing a lot of =
bike park riding.

SHOCK: I don't know about the rear shock. I never swapped out
mine, and I think the stock rear shock works okay. It would benefit
from rebound damping, so I would make sure that any rear shock you
consider has rebound damping. I wouldn't spend a lot of money here and personally wouldn't do anything that involves changing the linkage (way beyond my level of engineering ability).

FORK - a good fork is probably more important than rear suspension. A 
significant fork upgrade may be the thing that would make the
Scott feel much better (if it doesn't feel good already). I would definitely get 80-100 mm travel and an air coil. The spinner 300 fits the bill, but I don't know the price and in my
brief search (2 minutes just now), I could not figure out where to buy
one. The Suntour with air also would be okay based on reviews. I
think I would go with a 24 wheel fork from either company because a
longer fork will make the bike more slack (decrease the head tube angle) and make it better for descending. Never hurt to email Lil Shredders about price and availability, but I agree I probably would not put $400 into this.

Lastly, put lots of pads on your boy (knees, elbows, probably chest and
shoulders, and definitely a full face helmet)! Race face adult elbow
pads work perfectly as knee pads for us. Also, if you are not using
chair lifts, realize he will not be able to climb well on any bike. 
Even short climbs will seem long to him. Get a long bungee chord and
pull him up climbs (super cheap and not as tiring as you might think). 
Finally, feed him often - moods break down fast when they get hungry.


Cheers and good luck!

-Andrew


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## Andrew Reznick (Apr 15, 2014)

Will -

I saw you in the lift line at Jackson Hole! I was there with my boy on a Shredder. I'm also the same guy who declined to mail a Scott to you because I could sell mine locally on Craigslist. Small world. I wanted to stay and chat, but it was our last run and my wife was waiting for us in the parking lot....

By the way, your Scott looked awesome. By posting that I am a Shredder fan, I don't want to detract from anybody who has upgraded a Scott. For me, it just seemed too difficult. 

Cheers,
Andrew


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## rdblatch (Jun 6, 2008)

Thanks Andrew. 

I think we're going to take his bike up to the park as is this weekend and try it out. I noticed that the fork (which I thought was stock), has WAY more travel than his Spinner Grind Air on his Spawn Savage. The Spinner is maybe getting 1.4 inches (35mm). The fork that's on there is getting about 2.75 inches (70mm). It's not an air fork, but it may be just fine. Definitely disappointed with what I'm getting on the spinner. Maybe there's something else I need to do. But I understand the 300 is much better.

For the rear shock, I agree on the rebound damping. I can see already that he bounces quite a bit on the stock shock. That said, it moves pretty well for his weight.

Although I don't know much about the A5-RR1, if it's getting similar travel to the stock and has rebound damping, it might be worth the $75. Otherwise, maybe I'll go with the Genesis and be done with any shock/fork upgrades.

The only other thing is shifting. The current XT shifters are WAY too hard for him to push. Are there any kid-friendly shifters out there that I won't need to change the derailleur, etc?


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## Andrew Reznick (Apr 15, 2014)

Sounds like your Scott has already been hugely upgraded - even more than you realized. 

FORK: The spinner grind air that I have seen (was about a 2013) only got about 40 mm travel. That is why I did NOT include it as a recommendation. If you have 75 mm of travel already, you are doing very well. The reason I recommend air is that you can tune it to his weight, but if the spring works at his weight, great! Also be sure to clean/lube/rebuild the fork. This may make it work significantly better.

SHIFTERS: XT is a HUGE upgrade from the crappy revo-shifter that came with the bike. you don't get any better than XT, and it should not require too much pressure. Also, XT would not work with the Cassette that came with the bike, so you already have upgraded hubs, cassette, shifters, and derailleur. Score! 

I have noticed on my own bikes and my kids that shifters get harder to press over time. Replace the cables and housings and you should be fine. Also, kids get better at shifting at age 7-8 than at age 5-6.

BIKE MAINTENANCE ADVICE: maintaining 4 bikes for my family has been though (for twins, mine, my wife). I have had a tendency to slack on the kids bike maintenance figuring that they are light and don't wear/tear bikes as much. Unfortunately, they do. Especially in bike parks. A week or so in a bike park probably puts as much wear on a bike as a year of typical use (for people of all ages). This means you need to change brake pads, service shocks, tune derailleurs, check pivot bearings.... But if you do all this, then the suspension, drivetrain, and brakes will work noticeably better and you will be safer and haver more fun.


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## Andrew Reznick (Apr 15, 2014)

Another Fork point - the stock fork has about 40-50 mm travel, so if you have 75 already, it is probably not stock. 
-Andrew


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## Andrew Reznick (Apr 15, 2014)

DROPPER POSTS - I don't see any dropper posts on this thread. Just put Dropper posts on my kids bikes, and it has been great for their riding and mine. No more stopping while I raise or lower their seats because the quick releases are too difficult for them to do themselves. Also, no more leaving their seat down for shortish climbs because putting it up is just too much of a hassle. 

At age 6, their seats were all the way down, so this would not have made sense. By age 8, their seats are really high for climbing, down for descending, so this does make sense. Also, I plan to move the posts to their next bikes.

Highly recommend the Pacific Northwest Components "Rainier" dropper. It is 27.2 mm diameter which would fit the bike, 80 mm travel, easy to push lever, easy to install, high quality build - just as nice as my thompson elite. All for $275. 

Cheers,
Andrew


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## Will Fisher (May 12, 2015)

Andrew, haha small world, indeed! We were out in the Jackson area for the first half of the summer and had a blast. Now back home in NC and it's like an oven it's so hot. I almost passed out on my first ride back. But headed to Pisgah in the mtns in western NC this weekend. 




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## rdblatch (Jun 6, 2008)

rdblatch said:


> Thanks Will.
> 
> Besides the weight difference, what do you think of the A5-RR1 vs. the stock shock? Is it the same amount of travel? Seems like the stock is getting around 2 inches or so. The Risse Racing folks told me the Genesis would get about 2.5inches.
> 
> Thanks again.


Hey Will. Just wondering if you saw this. Would you (or anyone else) recommend the A5-RR1 over the stock shock? Do you actually lose travel with this upgrade (but gain dampening)?


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## rdblatch (Jun 6, 2008)

This build looks great, Paul. I just found out I could get the Spinner 300 20" for $135 shipped. How do you like it? How has the A5 been? Thanks.


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## rdblatch (Jun 6, 2008)

Andrew Reznick said:


> Another Fork point - the stock fork has about 40-50 mm travel, so if you have 75 already, it is probably not stock.
> -Andrew


Thanks for your replies, Andrew . I'm really not sure if it's the stock fork or not. The shape looks exactly like the stock fork, but it the decals were removed and new Rock Shox decals were added. I suppose it could actually be a Rock Shox fork, but I don't think it is.....I don't think they made or make a 20" fork. But I could be wrong.

I suspect it's been modified heavily with new springs and the like to get the ~70mm (although I really have no idea). It's incredibly plush......probably too plush right now. Watching my son ride down the street, he just bounces the whole way. I'd like something with that kind of travel (70-80mm), but a little beefier and adjustable. The Spinner 300 might work well for $135 shipped. Sounds like I may be better off going with the 24" per


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## rdblatch (Jun 6, 2008)

paulm7508 said:


> Here we go.....Forks on and already a big improvement. Oli has said he feels much more comfortable on the bike and seems to be much more confident on the down stuff!!


Hi Paul,
Is that the Spinner 300 24" or 20"?

I just got a Spinner 300 24" for my son to put on his Scott Spark 20 (thinking it would make the geometry a little more downhill ready), but the thing looks huge!! I'm debating whether I should've gotten the 20" and I should send it back before cutting. How does your son like it?


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## rdblatch (Jun 6, 2008)

Here's how my son's bike looked when I got it. I just added a KS A5-RR1. The Spinner 300 Air 24" is being installed this week. I'll try to post more once complete.

So far, the KS A5-RR1 doesn't seem much better than the stock shock (although I think it looks nicer). I suspect there will be some value over the stock shock, but I haven't found a way to mount it with full travel yet. Jury is still out.

I'm really not sure how the 24" fork will work/look. The thing looks huge. The tech at my LBS looked at me like I was nuts. I may need to reconsider before having it installed.


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## paulm7508 (Jan 3, 2016)

Hi Guys,

sorry been off this thread for a while, been interesting reading all the questions that have been posted.
Oli has been riding with his current setup for a couple of months now and I can report the following:
Rear shock (A5 RR1) - works well once you get the pressures right. I had issues with fitment due to the type of riding that oli does - whichever way I fitted it there was always going to be a valve contacting the linkage and limiting travel. the best option I found was to have the negative chamber on the linkage side but, after some large jumps/drops the valve actually came off. due to his weight this doesn't seem to have had an issue as the "rebound effect" the neg chamber was for has minimal effect

forks (Spinner 300 air) - this has been the best edition to the bike so far. the 24" has really improved the geo for downhill stuff and we are getting 70(ish) mm of travel on the 80mm setting.

all in the suspension setup has really helped Oli to improve, you just need to mess around with the pressures to find a setting that they like.


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## rdblatch (Jun 6, 2008)

Thanks Paul. We'll give the 24" a shot and see how it goes. Please let me know if you have any lessons learned for setup or determining the right pressure.


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## paulm7508 (Jan 3, 2016)

Hi rdblatch, as far as setup goes we took it out for a ride with a shock pump and saw what worked best! I'm not sure of Oli's weight but somewhere around the 25kg (50lbs) mark. the RR1 shock is set pretty low as can be super stiff, think is around 35psi, same for the fork at probably 50psi. we are away at the minute but when I get back I will find out exact pressures. All I will say is it is surprising how low you can run the pressures and still have it be too hard for kids their size! we are probably running them a little high anyway to soak up the bigger hits


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## rdblatch (Jun 6, 2008)

Thanks again, Paul. Here's the new build with the Spinner 300 24" and A5-RR1. The same thing happened to us with the negative chamber (within minutes) and it broke off. I agree though, it's probably better. It was limiting travel and I had it set basically at zero to make sure it would come all the way back. I like it better this way.

The shop couldn't figure out how to get the pin out in order to change the travel setting on the 300. The stanchions are currently at 90mm, but the travel is something less than that. We're getting about 65mm, which isn't far from what he was getting on his old fork......although it's much more adjustable now. I also agree on the 24" changing the head angle and making it better for downhill. We haven't tried it on a trail yet, but it definitely looks more stable.

We're sitting at about the same pressures as you too. Thanks again. Here's a pic of the new setup.


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## paulm7508 (Jan 3, 2016)

looking good rdblatch, amazing how the cange of fork completely changes the look and feel of the bike! 
We went for a ride at a local DH track over the weekend...thought the fork was perhaps a little too stiff at 50psi so let some out...turns out that 50psi is around the minimum pressure the fork needs to fully extend te fork legs after compression. how are you finding the pressures?


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## rdblatch (Jun 6, 2008)

Hey Paul. Thanks. We went to the downhill park on Sunday to try it out. It was great. The slightly changed geometry seemed to really provide a lot of extra stability for my son. 

In terms of pressures, I just checked and I had him running about 27 lbs on the fork and about 36lbs in the shock. It's pretty plush, but I think it needs to be for a 50lb kid. He still wasn't bottoming out on the fork. For me, it still comes back almost all the way......maybe a few mm less, but not much. So far, I'm pleased with it. 

What are you currently running the shock at? For me, that one doesn't seem to cone all the way back. I think that's more the general stiffness of the frame though.


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## Will Fisher (May 12, 2015)

Guys, regarding mounting the A5 shock, go back and look at the picture I posted. It's mounted upside down and backwards and I can easily access the valves


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## Will Fisher (May 12, 2015)

And I took a few links out of the chain and got rid of the chain guide. Saved almost 12 oz and haven't dropped a chain yet. 


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## jochribs (Nov 12, 2009)

PaulM and Rdblatch,

On the Spinner 300 Air 24...what's the travel you are set at, and what is the axle to crown measurement?

Thanks guys.


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## dobra (Sep 26, 2016)

hi warren569. can you tell me what the shock is and has it worked well.
cheers, mark


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## AmelieE (Aug 13, 2017)

*One more custom spark jr*

Hi, and thanks for all the inspiration. I first read some of this thread when we were starting to plan our own build. Now it's ready and I would like to share it with you guys
The build startet of with just a frame with broken gear hanger and a shock. So we basically started from scratch sanded an painted it. As a solution to the missing gearhanger we used internal gearing, that turned out great since our 5 year old now can gear whenever he like to. A good soulution for the riders how start realy young on their 20" bike.
We bould the weels from scatch, it was not easy to find good parts for it but it turned out great in the end.
To get the geometry more agressiv we used offset bushings to lower the bike and fited an awsome (but expensive...) 80 mm carbon fork from SR Suntour. For us that was enough since the bike are used for everything: skatepark, pumptrack, singeltracks, riding to kindergarten etc. in adittion to downhill we didn't want to make it to slack.
For handlebar we went with a flatbar to start with since the kid is realy smal everything else would be to high. We might change it to a riser when he grows.
Cranks are cut to 135mm, maybe he could had even shorter right know but we don't want to have to change them as he grow so we compromised. 
Generally we tried to keep the bike as light as possible (10,4 kg with pedals), as green and red as possible spend as little money as possible.

If you are intressted in the components most of them are listed here:
Scott spark-jr - johan.ericson's Bike Check - Vital MTB


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## Steve-XtC (Feb 7, 2016)

AmelieE said:


> Cranks are cut to 135mm, maybe he could had even shorter right know but we don't want to have to change them as he grow so we compromised.


Once you have shortened your first set it becomes a lot less intimidating to do another. 
I just added some 145's to the nearly 8yr old's XC bike though he's still on 140's on his FS. It took longer due to being hollow cranks which I had to progressively fill (aluminium epoxy used for car engine repairs) as I drilled .. let it dry the drill some more... but even with this actual time expended was <1 hour... the last solid cranks took around 30 minutes....

The new hollow Deore Cranks are yet to be fully tested but I saved the steel inserts from his Zee Cranks (now on his FS bike)) so I still have an option to drill these out wider and insert the steel thread inserts and use the aluminium epoxy to secure them in.

So you could easily take a step back and save the 135mm for later if they turn out too long.


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## jochribs (Nov 12, 2009)

AmelieE said:


> Hi, and thanks for all the inspiration. I first read some of this thread when we were starting to plan our own build. Now it's ready and I would like to share it with you guys
> The build startet of with just a frame with broken gear hanger and a shock. So we basically started from scratch sanded an painted it. As a solution to the missing gearhanger we used internal gearing, that turned out great since our 5 year old now can gear whenever he like to. A good soulution for the riders how start realy young on their 20" bike.
> We bould the weels from scatch, it was not easy to find good parts for it but it turned out great in the end.
> To get the geometry more agressiv we used offset bushings to lower the bike and fited an awsome (but expensive...) 80 mm carbon fork from SR Suntour. For us that was enough since the bike are used for everything: skatepark, pumptrack, singeltracks, riding to kindergarten etc. in adittion to downhill we didn't want to make it to slack.
> ...


 Good looking build, and you got your hands on an Axon Werx 20! Good work.



Steve-XtC said:


> The new hollow Deore Cranks are yet to be fully tested but I saved the steel inserts from his Zee Cranks (now on his FS bike)) so I still have an option to drill these out wider and insert the steel thread inserts and use the aluminium epoxy to secure them in.
> 
> So you could easily take a step back and save the 135mm for later if they turn out too long.


Steve when you say hollow are you referring to the 615's that are relieved on the backside? If so, do you have any idea (if you have the cranks) how thick the relieved section is? 8-10mm thick?


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## Steve-XtC (Feb 7, 2016)

jochribs said:


> Steve when you say hollow are you referring to the 615's that are relieved on the backside? If so, do you have any idea (if you have the cranks) how thick the relieved section is? 8-10mm thick?


I found the cut-off end and they are FC-M580.

I got them used cheap on ebay (without model) so I took a punt.. I was hoping they weren't hollow but then decided to try out my idea of the aluminium epoxy (that is advertised as being able to tap)

This went OK except it was difficult to drill with the hollow part... (and a hand drill) so I just progressively filled the hollow part with the epoxy, waited till it set and drilled out more.

I'll try and get a photo and measure the relieved section up if you like but its actually easily thick enough... his DMR V12's don't go all the way through and his Aest titanium ones are shorter and even less.

Someone else posted a photo a while back of FC-M780's that they had a hole drilled and a solid but of aluminium bar welded in place then drilled and tapped which looked pretty good... but unless you know a tame elder sounded expensive.


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## jochribs (Nov 12, 2009)

Oh gotcha. When you said Deore, I was wondering if you were referring to the 615's and 610's. They appear to be heavily relieved on the back side, but not exactly hollow. Wondering if there is enough material there to tap and hold a pedal. 

Your idea of filling and tapping actual hollow cranks is pretty brilliant.


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## Gangly1 (Jul 5, 2016)

Really nice build, please tell me you don't lock it up outside the kindergarten!


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## AmelieE (Aug 13, 2017)

Thank you for the advise, for now we stick with the 135 since he actually handels them good. For the next build we might try out your idea with the hollow cranks, let us know how it works out. 
How tall is your kid?


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## AmelieE (Aug 13, 2017)

Gangly1 said:


> Really nice build, please tell me you don't lock it up outside the kindergarten!


There are some positive sides with living in a really small and distant place


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## Steve-XtC (Feb 7, 2016)

jochribs said:


> Oh gotcha. When you said Deore, I was wondering if you were referring to the 615's and 610's. They appear to be heavily relieved on the back side, but not exactly hollow. Wondering if there is enough material there to tap and hold a pedal.
> 
> Your idea of filling and tapping actual hollow cranks is pretty brilliant.


We'll see how brilliant over the long term testing  
I used this: Technicqll Aluminium Cold Weld Metal Bearing Bolts Epoxy Repair Glue Paste 80ml | eBay

I've shortened Alivio's before with the concave back... and the question of how much metal seems possibly better answered by the Aest Ti pedals that have a shorter thread (which has been fine with the 50lb kid through numerous pedal strikes) 
Anyway the pedal thread only reaches about half way through a normal set of cranks and its been fine ... here are the same peals on the Zee Cranks
(I never finished the filing to make the ends neater as they have had crank protectors on the end)


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## Bassballer150 (Aug 9, 2017)

How do you like the alienation rims? I’m doig a build for my daughters Hotrock and I am in the process of sourcing the rims to build her a set of wheels so we can run a 9spd


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## paulm7508 (Jan 3, 2016)

The alienation rims are great, Ollie rides his Scott really hard and they have taken everything he has thrown at them. They may not be the lightest but they aren’t too bad


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## azraelvis (Sep 26, 2014)

hi everyone,
i'm sorry about digging out this old thread. but it is by far the best one i found about the spark jr.
i bought one für my 4 years old daughter, I think it will take 1.5 more years until she can ride it, so I got enough time for the build.
my plan is:
- repaint the frame. she wants purple.
- new wheels, disc brake f/r
- new fork, i already bought a 20" spinner grind air
- 1x9 or 1x10 drivetrain, new cranks
- handlebar, stem, everything..

so as you can see, in the end there will be only the frame left. 
many of you used a 24" fork, which makes the head angle more slack. I am going to use a work components angle headset with +1°. that will make 69° - better than 70° . Maybe I am going for a 24" fork, we will see how it works.

So at the moment I disassembled the bike. I removed all the cable holders and the canti socks, because for shure I am going for internal cable routing.
I am checking AliExpress for a wheelset. I have never build up a wheelset on my own before , and you get a 20" disc brake wheelset at Ali for 80 dollars. The problem with it is that all of the sets do have a 100 mm front and 135 mm rear hub - but the spark has only 130 mm rear. 
I will come back here and update you what happened. And of course ask several questions, because in Germany this bike does not seem to be that popular as it is here. 

Christian from Germany (sorry for poor english)


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## Kingfisher2011 (Nov 1, 2011)

Your english was solid sir! Now bring some pics!  Good luck with the build. Keep us posted on progress. I'm working on similar on a 26".


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## RMCDan (Feb 28, 2008)

Seeing as how you're in Germany, if it were me I'd cut my losses and buy a Propain Frechdax. Especially if you could find one of the older ones used that could covert to 16" wheels so she could ride it right now. That Grind Air fork is decisively inferior to the 1stRide Carbon on the Frechdax. Spawn also has EU distribution. Honestly, the custom Spark Jrs were cool in their time, but there are just way better 20" FS bikes available now.

All that said, good luck!


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## azraelvis (Sep 26, 2014)

I had an eye on the frechdax, but the problem is that you do not get used ones, and for the very special moment you find one it will be not under 1200,-. a new one is 1700,-. I did not pay that much for all of my bikes.
The spark is disassembled, i cut of the canti socks and cable holders. I also startet grinding of the paintwork. Next step is a friend of mine is going to sandblast the frame. 
And yesterday I ordered a 1° angle headset from works components (UK).


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## Steve-XtC (Feb 7, 2016)

Propain sell the fork separately, my sons friend is waiting for delivery of his Yuma but don’t know what he’s doing with the Frechdax .. he’s sponsored by propain so I guess it might belong to them 

I wouldn’t do internal cabling, it’s poor on many adult bikes designed for it* let alone the tighter angles it has to bend on a kids bike. As soon as it gets water and dirt inside it will make shifting horrible then impossible then you have to replace cables and outers (which I do every few months on kids bikes but I buy 10m of good outer at once) 

*some very expensive carbon frames have got it right to be fair 


Sent from my iPad using Tapatalk


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## azraelvis (Sep 26, 2014)

fasten your seatbelts, ladies and gentlemen!
this is fu****g crazy: he simply cut off the casting of a old fox talas and combined it with the double brigde of a boxxer:


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## RMCDan (Feb 28, 2008)

Wow, that's definitely some outside-the-box thinking.


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## robscaff (Jan 5, 2019)

my boys mongoose fireball 20 
full xtr groupset with shortened xtr crank arms from 175mm down to 152mm
carbon post
carbon bars
slx disk brakes
sun tour xcm air fork


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## azraelvis (Sep 26, 2014)

short update:
I got the wheelset, disc brake rotors and stem from ali express. I got the A2Z disc brake adapter and a pair of magura MT2 disc brakes. And I got some cranks - old shimano, cut down to 140 mm and some "weight tuning":


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## dookie (Sep 6, 2005)

Drillium baby!

Do the brakes work? Magura specs a thicker rotor (2.0mm) than the rest of the world (1.8).

Seems like a whole box of bandaids in use here...


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## Animal80 (May 3, 2019)

Hi, It's very much good information and knowledge in here. Glad I found this thread.

I just bought a Scott Spark JR 20'' full suspension for my kid her in Norway,
stripped it down, and started to rebuild it.
Need some part for the frame, bushings for the rear suspension. 
Tryed to talk whit scott but no help there.

Try to post some pictures, so you can see what i need..


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## Corban_White (Feb 5, 2019)

I replaced all the pivots in my son's Spark 24 a few months ago. My LBS was able to order the kit no problem (although it did take finding the right person who know how to get it done).


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## Animal80 (May 3, 2019)

Corban_White said:


> I replaced all the pivots in my son's Spark 24 a few months ago. My LBS was able to order the kit no problem (although it did take finding the right person who know how to get it done).


WOW, this was good news.

Is it possible that you maybe could get hold of some part numbers or something so i could.
Order it online, or give the parts number to my LBS


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## Corban_White (Feb 5, 2019)

I thought I had a picture of the package they came in but I can't find it. Sorry! I just told them I needed a pivot kit for a Spark 24 and eventually they got it ordered from Scott.


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## Animal80 (May 3, 2019)

Corban_White said:


> I thought I had a picture of the package they came in but I can't find it. Sorry! I just told them I needed a pivot kit for a Spark 24 and eventually they got it ordered from Scott.


 Okay, do they have a web site or mail address so i can contact them maybe? 

Also
Wonder if anyone knows how to service a Kind Shock ks A5-rr1 and 
Spinner 300 AIR 20"
Need some info about oil levels, or rebuild info.


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## azraelvis (Sep 26, 2014)

so sad that she won't accept "raw".


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## Animal80 (May 3, 2019)

azraelvis said:


> so sad that she won't accept "raw".
> 
> View attachment 1254931


I like it, wondering to do it. 
Have RAW alu on my bike


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## Animal80 (May 3, 2019)

Build some 16'' wheels whit disc to use this year to lower the bike. Now it hight is right for my little kid.









Sent fra min FRD-L09 via Tapatalk


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## Animal80 (May 3, 2019)

Doing rear shock mod.









Sent fra min FRD-L09 via Tapatalk


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## G-Force (Jan 5, 2007)

I found this thread after coming across a 2008 Spark Jr 20 for sale locally for $150 USD. Is that a good deal to start building up for my soon-to-be 6-year-old daughter now (and hold onto for my 3-year-old son to use in a few years)?


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## azraelvis (Sep 26, 2014)

of course it is. go on! soon ali express will be your best friend


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## azraelvis (Sep 26, 2014)

Suspension.
The project escalated at some point


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## RMCDan (Feb 28, 2008)

You can't not elaborate on that fork.


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## azraelvis (Sep 26, 2014)

painting is done.


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## nwa bike dad (Apr 21, 2018)

azraelvis said:


> painting is done.
> 
> View attachment 1269351


Beautiful!


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## KarmaBiker (Dec 24, 2007)

Beautiful job! Tell me about the fork!!!


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## azraelvis (Sep 26, 2014)

it is a spinner grind. I got them in 20" and 24", not sure which one i'm going to use.


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## G-Force (Jan 5, 2007)

Just made the deal and loaded it on the truck. My daughter is going to freak! I may be more excited than she will be. Let the custom build begin!


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## snowrydr01 (Aug 6, 2019)

i am picking up a 2011 (yellow) on saturday and am hyped! 

I didnt realized the stock drivetrain was freewheel 6sp with bolt on wheels. My sons GT was surprisingly better spec'd with freehub 7sp and QRs. First night is swapping over wheels, drivetrain, and cockpit since he is short. I have a full 10sp drivetrain in the parts bin so when the carbon bars and seatpost come in ill run a 9 of 10 setup and adjust out the rear mech to work. currently hawking a few used cranks to modify for the 1x front drivetrain and REALY like what some people have done here with the roller chain tensioner to get the chain up higher.


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## downhilldadUK (Aug 8, 2019)

Thanks for the inspiration guys , I am starting my build this week - I don’t think I’m going to do a full strip and repaint because I’ve got a fair bit of work to do and I like the oem paint job with stickers underneath the laquer which will take a lot to replicate at home, I have also bitten off more than I can chew with the fork build because I didn’t want to pay out £350 for the Propain fork and to me the Spinner looked like it would need work and it work that well from the comments so I’m doing my own fork for now and if that fails then I will get the RST or the Propain fork. 
One thing I really like is the SDG Slater kiddy handle bars - it always annoyed me that boy couldn’t get his hand around a standard thickness bar grip so SDG’s skinny bars will be a huge confidence boost as he will grip better while braking.
Wheels and headset and shock are coming from Aliexpress, I am looking out for a cheap fox shock too, forks wise I got a Maverick fork for £50 which I plan to cut crown off and use a set of fox 40 upper/lower crowns that i already have for quite a serious front end and less than 2kg ish. 

Thanks Thanks for the inspiration guys , I am starting my build this week - I don’t think I’m going to do a full strip and repaint because I’ve got a fair bit of work to do and I like the oem paint job with stickers underneath the laquer which will take a lot to replicate at home, I have also bitten off more than I can chew with the fork build because I didn’t want to pay out £350 for the Propain fork and to me the Spinner looked like it would need work and it work that well from the comments so I’m doing my own fork for now and if that fails then I will get the RST or the Propain fork. 
One thing I really like is the SDG Slater kiddy handle bars - it always annoyed me that boy couldn’t get his hand around a standard thickness bar grip so SDG’s skinny bars will be a huge confidence boost as he will grip better while braking.
Wheels and headset and shock are coming from Aliexpress, I am looking out for a cheap fox shock too, forks wise I got a Maverick fork for £50 which I plan to cut crown off and use a set of fox 40 upper/lower crowns that i already have for quite a serious front end and less than 2kg ish. 

Thanks Thanks for the inspiration guys , I am starting my build this week - I don’t think I’m going to do a full strip and repaint because I’ve got a fair bit of work to do and I like the oem paint job with stickers underneath the laquer which will take a lot to replicate at home, I have also bitten off more than I can chew with the fork build because I didn’t want to pay out £350 for the Propain fork and to me the Spinner looked like it would need work and it work that well from the comments so I’m doing my own fork for now and if that fails then I will get the RST or the Propain fork. 
One thing I really like is the SDG Slater kiddy handle bars - it always annoyed me that boy couldn’t get his hand around a standard thickness bar grip so SDG’s skinny bars will be a huge confidence boost as he will grip better while braking.
Wheels and headset and shock are coming from Aliexpress, I am looking out for a cheap fox shock too, forks wise I got a Maverick fork for £50 which I plan to cut crown off and use a set of fox 40 upper/lower crowns that i already have for quite a serious front end and less than 2kg ish. 

Thanks


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## snowrydr01 (Aug 6, 2019)

What aliexpress wheelset did you go with? I am considering the same thing?


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## snowrydr01 (Aug 6, 2019)

Will Fisher said:


> Sent from my iPhone using Tapatalk


Its a small detail but how are people mounting their Roller Chain Guide to the bottom bracket? Since its just a hole it looks like it would work fine on a BB30 but not sure how it works with an internal square taper? I pick up my jr 20 saturday so i dont have it in front of me incase its an obvious answer.


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## snowrydr01 (Aug 6, 2019)

what 26.8 seatpost are people using from aliexpress? I cant seem to find the correct size.


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## azraelvis (Sep 26, 2014)

Gentlemen, I have got a stupid question. I installed the shock like Will did. Half way of the travel the linkage touches the Main chamber valve. So I turned it around Like Paul did. Half way of the travel the link between the seat stray touches the negative chamber valve. In both directions I only geht half of the travel? How did you Guys manage that?


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## G-Force (Jan 5, 2007)

I don't have a set of calipers to measure the seat post diameter, and it's unreadable on the post. Can anyone sell me the size so I can source a new one?


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## azraelvis (Sep 26, 2014)

26.8 mm.


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## MJNMTB (Aug 20, 2019)

Thought I would share my daughters bike...

It does have a dropper post!

I sanded down a PNW Pine 27.2mm to 26.8mm. Works perfect!

All I need is a better rear shock. Does the KS work ok? Better than the stock coil pogo stick?


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## snowrydr01 (Aug 6, 2019)

care to share your sanding technique? I was going to sand down a 27.2 i had laying around but wasnt sure id be able to get a consistent diameter along the entire shaft.


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## MJNMTB (Aug 20, 2019)

I mounted the post in my bike stand and I used 80 grit to sand it down. I sanded down towards the end of the post on every pass.

I slowly rotated the post to keep the diameter consistent. 

Worked quite well actually.


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## G-Force (Jan 5, 2007)

Anyone running Brood Maxtion 20x2.20 on the rear? Checking for tire clearance on the rear triangle...


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## azraelvis (Sep 26, 2014)

much space. i run schwalbe little joe 20x2.0. btw the lightest off road tire i found. 410 g each.


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## G-Force (Jan 5, 2007)

azraelvis said:


> much space. i run schwalbe little joe 20x2.0. btw the lightest off road tire i found. 410 g each.


Are they tubeless?


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## azraelvis (Sep 26, 2014)

No. But even with tube much lighter than any other 20x2.0 tire you can find.


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## G-Force (Jan 5, 2007)

azraelvis said:


> No. But even with tube much lighter than any other 20x2.0 tire you can find.


Brood Maxtion 20x2.2 Tubeless are 440g.
https://spawncycles.com/brood-maxtion-22


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## paulm7508 (Jan 3, 2016)

azraelvis said:


> Gentlemen, I have got a stupid question. I installed the shock like Will did. Half way of the travel the linkage touches the Main chamber valve. So I turned it around Like Paul did. Half way of the travel the link between the seat stray touches the negative chamber valve. In both directions I only geht half of the travel? How did you Guys manage that?


Unfortunately i could not do anything to ensure the valve missed the linkage and, after a few weeks, the valve did break off. although not ideal, it didn't have too detrimental effect on the shock and the "rebound" action. The only way I could see to prevent it was to take some material out of the linkage....


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## paulm7508 (Jan 3, 2016)

I didn't imagine when i started this thread that it would still be continuing to this day! i'm glad that it has been a source of inspiration for people.

I thought it would be cool to share some pictures of the bike in use over the last couple of years. Suffice to say Ollie is now 10 years old and moved on to a bigger bike, but his Scott Spark Jr really served him well. It took everything he could throw at it - big jumps, crashes, plenty of race meets - and it is still in really good condition and has been passed down to his little brother.

A few things we have learnt with the bike;

1. great platform for a custom build. The frame is solid and, without having huge sums to throw at high-end kids bikes, holds up extremely well

2. Geo - putting a 24" fork up front gave it the perfect geo for downhill/enduro style riding. Frame is well braced so can hold up to it.

3. These bikes always get compliments! can't tell you how many offers I got to purchase the bike from us!

Anyway, here's some pics of the Scott..


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## paulm7508 (Jan 3, 2016)

.....and the new bike that Ollie has got as he won't stop growing!


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## azraelvis (Sep 26, 2014)

@Paul: the mechanic in my local bike shop found a solution. We shortened the valve of the negative chamber and prepared it to get filled with NOx. In the end it will be only a small cap and not be in danger to be cut off. Now everything fits.

As I told before, I used an angle headset (work components), +1 degree. With the Spinner grind 20" i measured 68° head angle.


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## G-Force (Jan 5, 2007)

azraelvis said:


> so sad that she won't accept "raw".
> 
> View attachment 1254931


What did you use to strip the paint?


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## azraelvis (Sep 26, 2014)

First sandpaper, then a sandblaster.


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## AJC223 (Sep 28, 2019)

Dear all, 

I’ve been following this thread with interest now for a while and it gave me the inspiration to purchase my sons SCOTT Spark JR. It’s bright red and in immaculate condition. 

Obviously it requires “upgrades” and I’ve built a good understanding for the previous posts but some help with some specific questions would be awesome. 

1. I was looking for the spinner grind air forks, but they seems to have disappeared in the UK. Does anyone know where I can get them from? 

2. I would like to fit disc brakes all round. Does the A2Z adaptor actually work? I’ve heard mixed reviews. 

3. If I fit disc brakes I will need new wheels. Any recommendations? The rear hub spacing is worrying me, is it 130 or 135mm OLD? And can the later be made to fit. Really helps with wheel choice. 

4. I intend to fit a zee rear mech and shifter paired with a 9 speed cassette and chain. Any issues? 

Any help gratefully appreciated and I look forward to posting some pictures once it’s all complete. 

Adam


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## G-Force (Jan 5, 2007)

AJC223 said:


> Dear all,
> 
> I've been following this thread with interest now for a while and it gave me the inspiration to purchase my sons SCOTT Spark JR. It's bright red and in immaculate condition.
> 
> ...


1. I reached out to Spinner USA about 2 months ago when I was sourcing one for the build I'm getting ready to start. The response was slow (about 6 days), but they did send me a very reasonable price (I think it was $150 USD, shipped to the USA). But between the time I reached out and the time he responded, one showed up on pinkbike.com for a lot less.

Use this link to reach out to them. Kogee Industrial Co.,Ltd - Spinner-USA

2. The A2Z DM-UNI is the one you want to use on the Scott Spark Jr. It mounted to the rear dropout plate perfectly on my. I've also read the reviews that you probably saw saying it didn't fit...those were all applications where different brand frames had tubing welded closer together near the dropout...not allowing the plates to "sandwich" together.

3. The hub spacing on my build is 130mm...pushing from 130 to 135 takes minimal effort. But that pressure is enough to side-load a bearing. Here is an inexpensive way to get those 5mm. I ended up getting a set of Koozer XM490's that I'm lacing up to Atomlab AirCorp Race Disc hubs. Just waiting on my Sapim spokes to get here so I can lace up the wheels. 




4. I was going to do a zee and 9spd. cassette on mine before I found someone locally that was practically giving away a SRAM X9 shifter and X9 Short cage rear and 10spd SRAM PG-1070 (11-36T)

Hope this helps... and will be makes some posts soon about my progress.


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## AJC223 (Sep 28, 2019)

Thanks G-Force, 

I’ve tracked down the European dealer for Spinner now, very reasonably prices. I’m going for the 300 Air 20. 

Thanks for the info ref wheels, I will look into that and I’ll keep an eye on 2nd hand SRAM X9, 

Thanks again

Adam


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## Livingston (Dec 16, 2008)

Thanks to all who gave me the inspiration to find and modify this Spark Jr. I found a used unmolested 2013 Scott Spark Jr 20 model in May for $125. I have a few more mod's but here is the current condition.









Upgrades:
Fork: RST 24" First
Shock: KS A5 RR1
Wheels: Trailcraft 20" disc
Tires: Brood Maxtion 20x2.20 from Spawn Cycles
Brakes: Mechanical TRP Spyke
Handlebar: An old aluminum thing I had laying around
Rear Derailleur: XTR M900 8spd
Cassette: Misc 8 spd from parts bin
Rear Shifter: Grip Shift 8 spd

Issues I've run into:

Shock:
The KS A5 RR1 will not fit in any orientation without modification to the bike. To fit the RR1 shock, I had to remove some aluminum from the seat stay link to clear the negative chamber valve. This does not affect the strength of the frame as the load is on the opposite side of the material removed and there is a lot of extra material there. (I am a mechanical engineer btw)









I tried flipping the links as that looked like an easy way to get a little more travel and raise the rear a bit to compensate for the 24" front fork. This required some more material removal from the seat stay link but the air can now touches the cable guides at full compression. I haven't clearanced the cable stops yet as I'm not sure about the gain from the link swapping. I want to take some measurements to see what the bb height change is, travel, etc. before making that mod. I am also not too impressed with the RR1 and might get the Risse for real dampening.

Linkages:
The problem here is that the barrel screws are too short. When you crank down on the mating screw, it squeezes things together too tight to rotate freely. Look how deep the barrel screw is in the middle of the link here:









It seems that Scott solely relied on thread locker to keep things together. I don't like that. I see that some have used longer bolts and locknuts to address the stickiness/binding in the links. Another option is to use "shoulder bolt lengthening washers". I used McMaster Carr p/n 91437A337, 8mm OD, 6mm ID, .031" thick. These match the OD of the barrel screw and fit over the M6 screw. So it essentially makes the barrel screw longer so you can properly torque the fasteners down for a metal to metal bottoming out yet spin freely. I think I used 2 on both ends of the shock connection and 1 at the rear seat stay links by the rear axle. Linkage was much smoother after this fix.

130mm vs 135mm rear axle:
I did remove the paint but not any metal, maybe a 0.5mm gain there. I did not feel any binding of the rear linkage actuation with the 135mm axle vs no axle at all so I am not going to worry about it.

A really fun project and so rewarding when we get out to ride.

Darren


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## azraelvis (Sep 26, 2014)

My rebuild is finished for the moment. We did the first rounds with the new bike, she likes the colour and the sound of the hub. I am very happy with what I've created. Maybe I am going to exchange the derailleur to a Saint or Zee with a short cage, the XT seems to be too long. At the moment I am waiting for the sun to come out to take some better pics.









(The kids bike is the one on the right side, left is my new Specialized Stumpjumper Evo... )


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## Animal80 (May 3, 2019)

azraelvis said:


> My rebuild is finished for the moment. We did the first rounds with the new bike, she likes the colour and the sound of the hub. I am very happy with what I've created. Maybe I am going to exchange the derailleur to a Saint or Zee with a short cage, the XT seems to be too long. At the moment I am waiting for the sun to come out to take some better pics.
> 
> View attachment 1295407
> 
> ...


NICE 

Sent fra min FRD-L09 via Tapatalk


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## paulm7508 (Jan 3, 2016)

azraelvis said:


> Gentlemen, I have got a stupid question. I installed the shock like Will did. Half way of the travel the linkage touches the Main chamber valve. So I turned it around Like Paul did. Half way of the travel the link between the seat stray touches the negative chamber valve. In both directions I only geht half of the travel? How did you Guys manage that?


I couldn't find a way to mount it without it interfering with either the shock casing or the negative valve, (unless you want to modify the frame, but didn't fancy that!), so in the end Ollie snapped the negative valve off the shock. Not ideal, but he didn't seem to have an issue with the lack of "rebound" control.


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## paulm7508 (Jan 3, 2016)

azraelvis said:


> Gentlemen, I have got a stupid question. I installed the shock like Will did. Half way of the travel the linkage touches the Main chamber valve. So I turned it around Like Paul did. Half way of the travel the link between the seat stray touches the negative chamber valve. In both directions I only geht half of the travel? How did you Guys manage that?


Hi Azraelvis, with the way i mounted it, (only option as I saw it other than to modify the frame), Ollie ended up snapping the negative valve off the shock. Not ideal, but he never missed the "rebound" control that it should have offered....


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## smithers166 (Apr 24, 2018)

Hey guys, I saw one of these little bikes locally and I am planning on building one up. I also found a 24 in and plan on doing a side by side build. I am hoping to pick up the 20 on friday to get my first real look at the bike. 

I dont have any children myself but I like to tinker, have the time, and enjoy building bikes. Hoping to offer these bikes a 2/3 the cost of new bikes on the market. Also exploring options to just donate them to the local bike club for trial bikes or further donation. Lots of avenues to explore. What has been great is reading through this forum getting me stocked to build something.

For my build I'm exploring the Sid fork on the 24 and probably the suntour 24 air fork on the 20. The spinners are hard to find.

Wheels and cranks I may just go with spawn cycles. The wheels seem light enough for the price and I e never built a wheelset before.

Rear shock I am not sure I'll go with the A5 since people have issues breaking stuff off of them. So I may look for the 140x25 fox shocks. Some questions I have since I havent seen them in person yet is would it be possible to drill a section out of the seat stay linkage where it attaches to the lower link, drill the holes all the way through and attach the shock there. More leverage, more stanchion travel might work out to a stock sizing shock. Again, I need to do some measuring. I also briefly researched grinding off the forward shock tabs and relocating them forward a bit but I think it would be too much a hassle to heat treat the tiny frame. 

Finishing kit I'm looking at a full compliment of the sdg junior kit. Put one on my nephews bike and he loves how grippy the pedals are and the size of the grips. Probably shimano br395 brakes. Used them on adult bikes and they are great. And chinese carbon seatpost to save weight. 

Let me know what you all think.
Cheers


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## smithers166 (Apr 24, 2018)

Hey all, if anyone needs a bushing kit I found a company that sells each piece but I had to order sets for the minimum price.

Steel Backed PTFE Lined

This is the place I found them. They will have to be modified with a dremel slightly or you can pay them extra for exact sizes.

Cheers


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## Animal80 (May 3, 2019)

smithers166 said:


> Hey all, if anyone needs a bushing kit I found a company that sells each piece but I had to order sets for the minimum price.
> 
> Steel Backed PTFE Lined
> 
> ...


Hi.
WOW, this is good news 

Relay want to order some.
Have you measured the sizes?

Best regards..

Sent fra min FRD-L09 via Tapatalk


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## smithers166 (Apr 24, 2018)

Yes, I took the ones out of the 20 in frame I have. I spoke with the sales rep there and found something that closely matches the stock ones. The seat stay pivots need to be cut down. Or they can cut them for you. I'll have a spare if you want to purchase them off me.


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## Animal80 (May 3, 2019)

Nice, sounds good 
I from norway,
I can pay whit paypal?

Sent fra min FRD-L09 via Tapatalk


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## MJNMTB (Aug 20, 2019)

I am selling my daughters Scott Spark for anyone interested.

https://orangecounty.craigslist.org/bik/d/el-toro-2004-scott-spark-jr-20-fs/7128833760.html


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## helevalge (Jun 5, 2020)

Hi everyone!

Writing from faraway Estonia 
I was inspired by your custom Spark 20" bikes, so I´m in process of building my own. I have two sons (6 y.o and 4 y.o), who are crazy about mtb. 

Question about 130 mm rear hub - how about using road rear hub like f.ex Shimano Sora? It´s O.L.D is 130mm and it fits 8/9 speed cassette, so would not need any frame adjustments. 

Thank you in advance!


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## G-Force (Jan 5, 2007)

You could...but then you're limiting yourself to only rim brakes. I wouldn't let 2.5mm on each side keep you from using a 135mm disc hub.


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## smithers166 (Apr 24, 2018)

I found a set of novatec hubs from China that are 130mm disc. (Well that's what they said) so I'm gonna try those along with some alienation mischief rims that are tubeless ready and 28h. Question is should I go 2x or 3x cross on the spokes? 

The builds are coming along great. Frames are painted and I just put decals on. I'm excited to get them fully built.


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## smithers166 (Apr 24, 2018)

https://photos.app.goo.gl/NJyoV4k5MDdBnNXi6


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## smithers166 (Apr 24, 2018)

I also found a new shock to use that has rebound damping. It is a kind shock 291R coil at 125x18mm. So you lose a little bit of travel but get damping. Going to try that on the 24in bike.

Weights
291R- 375g
Stock shock- 291g
A5 RR1-179g


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## helevalge (Jun 5, 2020)

Decided to go with disc-brakes and adapter, so 135 it is...


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## azraelvis (Sep 26, 2014)

final stadium. I changed the derailleur to a 10speed saint. 9,82 kg.


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## helevalge (Jun 5, 2020)

The bike is absolutely beautiful!

Could you plz tell me what kind of rear shock did you use? 
I´ve ordered A5 RR1 from aliexpress ages ago and never got it, so now looking for other variants.


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## azraelvis (Sep 26, 2014)

its a Kind Shock A5. But I would give that coil shock mentioned above a try because of the rebound.


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## helevalge (Jun 5, 2020)

I finally got my KS A5-RR1 rear shock.
But now i am facing a bizzare problem - the fitting holes at the ends are orientated in a slightly different direction. If i align rear holes horizontally, then front ones are at a small angle to horizontal plane. Because of this i can´t fit the rear shock to my bike, barrel screws won´t go throught.

Any suggestions? Has anybody taken this shock apart to adjust?

UPDATE: local bike mechanic was willing to use raw force and is going to streighten it up.


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## smithers166 (Apr 24, 2018)

I was just going to say just stick a long screwdriver through it and rotate the "damper" body. I had to do that also, the holes were straight in there. I did take one apart. You need a huge wrench. My monkey wrench I used just marred up the plastic. It is just a piston on the inside. Nothing else.


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## smithers166 (Apr 24, 2018)

Getting almost done with one of the bike builds, Just have to shorten a couple hoses. But it was looking so good i had to take a photo. Finally coming together. I'm still waiting on hubs from china for the 20 in wheel build.

I'll try and grab a weight soon.


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## azraelvis (Sep 26, 2014)

That is 20 Inch?


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## smithers166 (Apr 24, 2018)

24, but I have an identical 20in I'm building right behind it. Waiting on hubs to build wheels.


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## azraelvis (Sep 26, 2014)

My 24" project is a Specialized Hotrock FSR:


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## helevalge (Jun 5, 2020)

Frame painting is done. Time to start mounting everything up. 

I decided to go with frame modification, that Darren suggested - I took some metal off to clear space for rear shock valve. Haven´t tested it yet though...


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## PmmPereira (Aug 14, 2020)

*New ride for my riding pal!*

First of all I want to thank everyone for the inspiration to build my son his new ride.
After finding a good deal on a Spark JR20 and some homework, he is very happy with the result, although it is still not finished...
Used some parts I had in the garage:
3T Jammin handle bars, XT 8Sp shifter, 8Sp cassette and Alivio derailleur.
Also fitted the Clarks M2 brakes with 160mm rotors after building a new support for the rear caliper.

The Odi Mini Ruffian grips, 135mm custom cranks and N/W chainring are next.


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## helevalge (Jun 5, 2020)

*Job done!*

Hey everyone!

I´ve finished with scott spark 20" for now. Kids are already out and testing...

During this long bike building journey I had lots of help from a local bike mechanic, so thanks to him!


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## smithers166 (Apr 24, 2018)

Looks awesome!! The color is popping!!


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## cc100fires (Oct 1, 2020)

*Thanks for inspiration and tips. Finished as well*

Finished my sons bike as well.

Fun project and well worth it... he loves it and everyone that sees the bike loves it.
the green photo shows the early stages, with minor mods and a Spinner grind 20" fork. Now running 24" Spinner 300 fork.
cranks are 127mm from Spawn Cycle. Shimano UN300 sealed bottom bracket... Reverse saddle. Deity handlebar and copperhead stem. Brand X sealed headset. Shimano Mt200 brakes and A2Z adapter in the rear.

local car body repair, re-sprayed the bike, and decals from local supplier.


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## parapa (Jun 14, 2021)

some work to be done  
replacement fork, damper, cassette


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## JTO (9 mo ago)

This is my build. It was for my son's birthday:

Scott Spark Jr 24 2014 frame, sand blasted the old paint and powder coated with the new pearl red color
Shimano SLX M7000 Upgrade-Kit - 11-speed 
1.0 Degree EC34-EC34 Angle Headset
Manitou Markhor suspension fork QR 9mm matte black 100mm 26inch 1 1/8
Exa Form A5-RE Shoock
Shimano Tektro brakes from an old Kona Stuff 2-4
Alexrims DM24 from an old Kona Stuff 2-4
Ritchey Trail Stem Ø31,8 0° black
Nukeproof Urchin Youth Pedals
Nukeproof Urchin Youth Saddle Red One Size
Nukeproof Urchin Youth Handlebar Red
Race Face Narrow Wide 32T ,104mm, 9/10/11/12
Shimano SM-RT56 Brake Disc (Diameter 160mm) 
Shimano Deore XT BL-M8000 Brake Lever Fram black
Shimano Deore XT BL-M8000 Brake Lever Bak black
Maxxis Minion DHR II 24x2.30" TR EXO Dual 60 Folding Tyre
Schwalbe AV 10 Tube for 24"
Maxxis Snyper 24x2.00''
Sram MTB Locking Grips with Two Clamps and End Plugs - Red
Shimano BB-UN300 Square Taper Bottom Bracket BSA 73mm incl. Crank Bolts

Kudos to @helevalge who had been helping out with this project!


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## Darth Lefty (Sep 29, 2014)

Fancy!


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## yakswak (Apr 17, 2004)

Very nice! How is that Markhor fork working out for your son? Considering it for a build for my kid, wanted to know if the valving in the damper and neg spring get in the way for lighter riders...



JTO said:


> This is my build. It was for my son's birthday:
> 
> Scott Spark Jr 24 2014 frame, sand blasted the old paint and powder coated with the new pearl red color
> Shimano SLX M7000 Upgrade-Kit - 11-speed
> ...


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## JTO (9 mo ago)

yakswak said:


> Very nice! How is that Markhor fork working out for your son? Considering it for a build for my kid, wanted to know if the valving in the damper and neg spring get in the way for lighter riders...


Hi @yakswak 

My son is 9,5 years old and not that heavy, but the fork works great even for his low weight and very low air pressure. I think it is very good price/performance fork fitting old bikes.
However I should mention that we haven't tested it properly yet, the season here is just starting....


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