# Crank length on kids bikes



## Fargo1 (Oct 19, 2012)

Last night I came across this article talkinga about short crank lengths for kids. Determining Crank Length for Children

It made a lot of sense to me. So I decided to check on the crank length of the 24" Raleigh Mtn Scout I just picked up for my kid. I was astonished to find that it had a 165mm crank on it. Thats what I put on my wifes 29er. It seems way too long for 6-10 year old kid the bike was 'designed' for. Looking at specs on bikes from Trek and Specialized I see they run a shorter 152mm crank. That seems more reasonable to me. So why did Raleigh use such a long crank. (I guess,y because they stock them for other bikes)

Anyway, is the above article accurate? What are your experiences with crank lenghts on kids bikes? Should I be looking at getting a shorter crank for my kids bike? If so where do you find parts for kids 24" mountain bikes? This bike is a bit of a build project so I will be needing some other items as well.


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## silvascape (Sep 11, 2014)

I am a bit of a advocate for making sure crank length is right for kids. IMHO it makes a huge difference to their comfort on the bike, stamina and riding skill. Kids riding with cranks which are too long need to shift their body weight from side to side to reach the bottom and top of the pedal stroke effectively. This makes bike handling very hard. Look out for hips moving from side to side when standing up peddling. When sitting look at the knee angle when at the top of the peddle stroke. Compare to yourself or your wife. However if your child is super tall for their age then 165s might be ok. 10%of height is a decent starting point when selecting crank length but obviously some people have long or short legs for their height. 

From what I have seen a lot of manufacturers (particularly in bmx) install cranks which would suit the tallest possible rider of that size bike. Makes no sense to me. From what I have observed your average 6 year old needs 125 to 130 mm cranks and your average 10 year old will ride 145 to 150mm cranks but once you get to age 10 their is a huge variation in height between kids. My tall for his age 5 year old has 120mm cranks on both his 20" bmx and 20" mountain bikes which works well for him.


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## Fargo1 (Oct 19, 2012)

I've always wondered why my 6 year old could out ride my 8 year old. He has a lighter bike, but with shorter cranks. I always thought the longer crank would be an advantage to the older kid. Even if the bike was heavier. But now I think the lighter bike along with the shorter crank is actually a much better setup.

Anyway, my oldest was only about 51" tall last time I measured him. So at 10% of height that puts him at about 130mm cranks. A long ways from 165mm. So I think I need to either switch cranks or get a different bike. He just got the bike this weekend, so I hate to change bikes right away. But I could since we picked it up used.

The bike is pretty light because it has a rigid aluminum fork instead of suspension. So I'd kind of like to just build him a nice light bike. Where is a good place to find cranks or cranksets for his bike. This is the bike he has
Raleigh Bicycles Mtn Scout - 2011 Youth

I can't seem to find anything for a 24" bike at the bike places I look for my 29er. So any help in getting the proper crank is appreciated.


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## XJaredX (Apr 17, 2006)

I've been going thru this, our Trek Superfly 20 came with 150 mm cranks which we took off right away and installed some 102mm ones we had which worked OK until the new cranks came in, which are 120mm. 

I actually used the website you linked to. I'd rather my 5 y.o. not get knee injuries from too long cranks.


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## Fargo1 (Oct 19, 2012)

I was just watching my kid on his new bike. When he stands up to pedal, his hips move like a hula girl. I think shorter cranks are a must. But now i have to find some at a decent price.


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## Fargo1 (Oct 19, 2012)

XJaredX said:


> I've been going thru this, our Trek Superfly 20 came with 150 mm cranks which we took off right away and installed some 102mm ones we had which worked OK until the new cranks came in, which are 120mm.
> 
> I actually used the website you linked to. I'd rather my 5 y.o. not get knee injuries from too long cranks.


Yeah, I injured my knee 2 years ago biking and its still not healed. I don't want my kids to face that. I think I really need to do this.

I also came across this website that has addional links to pages I haven't read yet. Custom Cranks | Zinn Cycles website This website is advocating longer cranks. But I think they are talking more about taller than average riders, because they also talk about shorter cranks for shorter riders. The biggest thing I think is to get the proportions correct. The give some formulas there too. Using his formulas my kid should have a 120mm crank. Which seems a really short to me. So I have some questions if the formula is that accurate across the range from kids to tall adults. But even if its not super accurate, it still shows my kids should have a crank much smaller than 165mm.

This has really got me thinking. I'll have to do more research and calculating, but I think a crank somewhere around 130mm to a max of 152mm would seem reasonable.

So where can I find cranks of this length? Will I have to replace the whole crankset or just the arms. I'm pretty new to all this yet.

Thanks.


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## XJaredX (Apr 17, 2006)

What type of bike is it? And how many teeth are on the front ring?

Most kids bikes are square taper cranks. So you can ask your LBS what they can get for you, it will be from the BMX world- or you can order online, whatever your preference.

In my case, I specifically wanted Sinz cranks for the pricepoint, and my LBS couldn't get Sinz, so they said order online, I got them from here:

BMX PARTS - Cranks - Crank Arms - SINZ Aluminum Square Crank - J&R BMX Superstore - BMX Bikes, Parts and Gear- Custom Bikes and Wheels

Now, I asked about how big the front ring was because my son's stock crank was a 32T- the smallest ring one can fit on a 5 bolt 110mm BCD crank is a 34T ring. A lot of kids bikes come with 32T crank, but I was unable to find any cranks aftermarket with 32T capability. My son will be ok with 34T though, his bike is a 7 speed.

Spawn Cycles told me that they hope to have 127mm cranks with 32T rings available by the end of this year, but nothing yet.


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## Fargo1 (Oct 19, 2012)

XJaredX said:


> What type of bike is it? And how many teeth are on the front ring?
> ...
> Now, I asked about how big the front ring was because my son's stock crank was a 32T- the smallest ring one can fit on a 5 bolt 110mm BCD crank is a 34T ring. A lot of kids bikes come with 32T crank, but I was unable to find any cranks aftermarket with 32T capability. My son will be ok with 34T though, his bike is a 7 speed.
> 
> Spawn Cycles told me that they hope to have 127mm cranks with 32T rings available by the end of this year, but nothing yet.


His bike is this Raleigh Mtn Scout. Raleigh Bicycles Mtn Scout - 2011 Youth I think Raleigh just threw on whatever parts they have available. His has a 165mm crank and an 80mm stem, in 2014 they had a 127mm crank and a 60mm stem. There is no consistancy on the bikes. Its crazy. They obviously didn't care what they put on the kids bikes.

Anyway, his crank appears to be a 4bolt setup with 3 rings. The specs call it a 'Pro Wheel 24/34/42t'. I don't know what you call the style of bottom bracket, but it looks like the bearings are internal and they screw in.

So I'm not sure if I will have to purchase a new crank or just arms. Honestly, if the price isn't too much I wouldn't mind converting him to a light 1x7 setup. He won't like giving up the extra gears, but it will be simpler for him.


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## Demo9 (Nov 20, 2006)

Check this company out https://www.facebook.com/turn3racing

They offer 4 x 104bcd spiders as well as 5 x 94bcd spiders.

You will need to get a new bottom bracket. My guess is a 68x116 or a 68x118.

I have a set of these cranks on my sons bike with a RaceFace Narrow Wide 30T ring running a 68x116 bottom bracket and a 11x36 10spd rear cassette. The chain line is pretty good with this setup. Turn 3 also offers the Answer Ti Slider bottom bracket if you feel like spending the extra $$ I have been running 135mm cranks on all our 20" bikes for the last 3 years. I have found that is an ideal crank length for the kids riding this size of bike.


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## ladljon (Nov 30, 2011)

I'm running 125mm on the road bike and 135s on the CX and mtb...5' sometimes wonder how many more races I could have won if I had done this years ago....


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## Fargo1 (Oct 19, 2012)

Demo9 said:


> Check this company out https://www.facebook.com/turn3racing


Those look nice, but at $140 for the cranks plus having to purchase a new bottom bracket the price is too prohibitive. At that point it would be cheaper for me to buy a different bike with better specs and sell this one.

ladljon - did you drill out those cranks yourself? I thought about doing that, but I'm not sure I would get a strait enough hole.


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## ProjectMayhem (Aug 23, 2013)

This is a very interesting discussion. My almost 4 year old (98cm tall) still has 89mm cranks on his bike. I have some 102s ready to put on (thank you!) when he needs them.

I think I need to measure his inseam and look at some formulas to see if he has grown enough. I also desperately need to swap his 22tooth chainring for something bigger so would be handy to do both at the same time.


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## XJaredX (Apr 17, 2006)

Fargo1 said:


> His bike is this Raleigh Mtn Scout. Raleigh Bicycles Mtn Scout - 2011 Youth I think Raleigh just threw on whatever parts they have available. His has a 165mm crank and an 80mm stem, in 2014 they had a 127mm crank and a 60mm stem. There is no consistancy on the bikes. Its crazy. They obviously didn't care what they put on the kids bikes.
> 
> Anyway, his crank appears to be a 4bolt setup with 3 rings. The specs call it a 'Pro Wheel 24/34/42t'. I don't know what you call the style of bottom bracket, but it looks like the bearings are internal and they screw in.
> 
> So I'm not sure if I will have to purchase a new crank or just arms. Honestly, if the price isn't too much I wouldn't mind converting him to a light 1x7 setup. He won't like giving up the extra gears, but it will be simpler for him.


The crank is one half of the arms- so you'll need to purchase a new crank. The Sinz I bought was $50. It is single ring though. Then I had to buy a ring which was like $20. And a chainguide which I assume is like $20, I haven't got the bill yet from my shop.


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## ladljon (Nov 30, 2011)

I had a machinist drill and tap the threads..and then I cut off the ends and machined them down....He charged me $100 for two pairs....I know that there are two peeps doing them for $90 for one pair. Just google short bicycle cranks. Check out Bikesmith Design and Fabrication....


Fargo1 said:


> Those look nice, but at $140 for the cranks plus having to purchase a new bottom bracket the price is too prohibitive. At that point it would be cheaper for me to buy a different bike with better specs and sell this one.
> 
> ladljon - did you drill out those cranks yourself? I thought about doing that, but I'm not sure I would get a strait enough hole.


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## tigris99 (Aug 26, 2012)

XJaredX said:


> I've been going thru this, our Trek Superfly 20 came with 150 mm cranks which we took off right away and installed some 102mm ones we had which worked OK until the new cranks came in, which are 120mm.
> 
> I actually used the website you linked to. I'd rather my 5 y.o. not get knee injuries from too long cranks.


trek superfly 20 comes with 127mm crank. Either u measured incorrectly or someone put the wrong crank on it. Crankset length is measured center of hole for bb to center of whole for pedal spindle. Wanted to point this out since u said ordered a 120mm, chances are it'll be a hair shorter than the stock one.


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## XJaredX (Apr 17, 2006)

tigris99 said:


> trek superfly 20 comes with 127mm crank. Either u measured incorrectly or someone put the wrong crank on it. Crankset length is measured center of hole for bb to center of whole for pedal spindle. Wanted to point this out since u said ordered a 120mm, chances are it'll be a hair shorter than the stock one.


No waayyyyy. The stock crank is giant. We measured it at my LBS and then for the heck of it I held the 120mm's I bought up to them.

I appreciate the input but I do know how to measure a crank- maybe you are in a different country where they spec them differently from in 'murica?


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## silvascape (Sep 11, 2014)

XJaredX said:


> No waayyyyy. The stock crank is giant. We measured it at my LBS and then for the heck of it I held the 120mm's I bought up to them.
> 
> I appreciate the input but I do know how to measure a crank- maybe you are in a different country where they spec them differently from in 'murica?


In complete agreement with XJaredX here. Trek superfly 20 bought in Australia - stock crank length = 150 mm. Way too long.


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## ProjectMayhem (Aug 23, 2013)

Just checked Islabikes and the small framed 20" bike comes with 114mm cranks, the larger one comes with 127mm cranks.


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## XJaredX (Apr 17, 2006)

ProjectMayhem said:


> Just checked Islabikes and the small framed 20" bike comes with 114mm cranks, the larger one comes with 127mm cranks.


that's actually what made me decide on 120 millimeters, I split the difference for my so who is 5 and a half. that put me basically, after I measured him, in line with the article at the top of this post.


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## tigris99 (Aug 26, 2012)

Ok well something went grossly wrong at the factory for the cranks then cause I measured my sons last night before u posted my reply to get exact number. They were supposed to be specced with 127mm crankset which is what my sons has. Oh and I live in Illinois lol. But could be possible my lbs caught that issue and had it corrected, hes good like that. 150mm in a 20" bike...had that happened to us I would have been all over Trek over that one. Owner of my Lbs used to be a rider for Trek and his brother works for Trek at their home office in Wisconsin. Been good for me as if I have had a complaint or warranty issue, its handled QUICK!!!.

All that being said, Trek listens, in my experience (yes I've dealt with them via email prior to learning connection my lbs has.) So all of you that have gotten hosed on that need to complain to Trek directly. At the very least it'll get changed, if not those that complain get a proper crankset. Put it this way, part number spec is precaliber 127mm crankset except with 6-8s stamped ring instead of ss ring.
Sent from my Nokia Stupid Phone using Tapatalk


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## silvascape (Sep 11, 2014)

If you go to treks website and pull up the Superfly 20 page there is several bike reviews complaining about how stupidly long the cranks are speced on this bike. Pretty sure trek is aware of the issue if they leave the complaints up on there website. I am lucky, my lbs knew of the issue and changed the cranks to trek dialled ones before we picked up the bike.


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## ProjectMayhem (Aug 23, 2013)

Just picked up a 2010 Scott Voltage JR 20 for £40 ($65), the cranks on it are 140mm. Do you think 102 would look really short on it...


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## XJaredX (Apr 17, 2006)

Nope. I had my 102 Spawn cranks on my son's bike and it looked just fine. I just bought 120's though for him but he was fine on the 102's.


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## ProjectMayhem (Aug 23, 2013)

Fantastic! Do I remember you have/had a Scott Voltage jr? It doe have a square taper bb, doesn't it? So many bike projects on the go atm I don't really want to start swapping bbs.


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## XJaredX (Apr 17, 2006)

Sorry, we've got a Trek Superfly 20 (also square taper).


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## POAH (Apr 29, 2009)

Turn3 Racing said:


> Turn3 Racing makes square taper cranks 100mm to 155mm
> Www.facebook.com/turn3racing


they also spam the **** out of forums with unpaid adverts :lol:


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## fanofcycling (Aug 11, 2009)

Just saw this post and thought this would be relevant.

Cranksets, Worth the weight? - Pello Bikes


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## LewisQC (Jul 3, 2013)

For those still wondering if shortening crank is worth it... My brother and I bought 2 SRAM s600 crank for our kids. My brother's son is really small for his age but really confortable on a bike. He just moved on a 20". The 132mm crank are not that big but for him it is now night and day with even smaller crank (I think it's 102cm). He cleared, on his first try with new crankset, a big climb that he had to walk every ride before. He called me tonight to tell me how he likes these cranks!!

My son is 135cm so we went with 135 cm. Beside less fatigue while climbing, the noticeable change is his ability to spin a lower gear without loosing balance. I feel like he has more control, less movement on the bike at slower speed. I had to change the bb to a squaretapper but in a year I'll put the original crankset and bb back on the bike...


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## Steve-XtC (Feb 7, 2016)

LewisQC said:


> For those still wondering if shortening crank is worth it... My brother and I bought 2 SRAM s600 crank for our kids. My brother's son is really small for his age but really confortable on a bike. He just moved on a 20". The 132mm crank are not that big but for him it is now night and day with even smaller crank (I think it's 102cm). He cleared, on his first try with new crankset, a big climb that he had to walk every ride before. He called me tonight to tell me how he likes these cranks!!
> 
> My son is 135cm so we went with 135 cm. Beside less fatigue while climbing, the noticeable change is his ability to spin a lower gear without loosing balance. I feel like he has more control, less movement on the bike at slower speed. I had to change the bb to a squaretapper but in a year I'll put the original crankset and bb back on the bike...


It amazes me the numbers of people who have never tried an appropriately sized crank that dismiss the effect it has.

Loads of people will say never ever put your kid on a bike that's too big yet completely ignore the crank size.

Having tried both I can say with some certainty that a slightly too large frame has way less negative effect than way too long cranks on the right size frame.

From my own observations I'd say even if you do nothing else to a 30lb monster stock bike changing cranks is the best upgrade for them actually riding properly.


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## pharpe (Mar 24, 2017)

I'm building a 16" Specialized Hotrock for my 4.5 yo son and I'm not sure about the crank. It currently has an 89mm crank. My son is 41" (1041 cm) tall with a 16" inseam. Using the conversion of 9.5%, indicated in the article, that equates to a 99mm crank. Spawn sells a 102mm. 

Question is should I leave the 89mm on for now? Would the short crank make it easier for him to learn on? I could then upgrade when he gets a little bigger. Or would the shorter crank actual make learning to ride harder?


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## thesmokingman (Jan 17, 2009)

pharpe said:


> I'm building a 16" Specialized Hotrock for my 4.5 yo son and I'm not sure about the crank. It currently has an 89mm crank. My son is 41" (1041 cm) tall with a 16" inseam. Using the conversion of 9.5%, indicated in the article, that equates to a 99mm crank. Spawn sells a 102mm.
> 
> Question is should I leave the 89mm on for now? Would the short crank make it easier for him to learn on? I could then upgrade when he gets a little bigger. Or would the shorter crank actual make learning to ride harder?


I would leave it and shorter is the lesser of two evils. The shorter cranks would actually be easier to pedal on echoing the posts above.


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## pste (Apr 13, 2017)

So my daughter has IBEX's 20" Alpine 320k and I've been noticing that she just didn't seem to fit right on those cranks. Now I look at it, and she's 4'2" with 152mm cranks, which is crazy. I think I understand why she's never really been able to pedal while standing on the bike. Is Spawn the best place to look for 125 - 130 mm cranks?


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## thesmokingman (Jan 17, 2009)

pste said:


> So my daughter has IBEX's 20" Alpine 320k and I've been noticing that she just didn't seem to fit right on those cranks. Now I look at it, and she's 4'2" with 152mm cranks, which is crazy. I think I understand why she's never really been able to pedal while standing on the bike. Is Spawn the best place to look for 125 - 130 mm cranks?


https://smile.amazon.com/Redline-Microline-Crk-Arm-130Mm/dp/B00FFYYD7C/

These cranks are still darn cheap. When I got my set 4-5 years ago they were 31 bucks.


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## pste (Apr 13, 2017)

Hmm... the bolt holes on the right arm don't look compatible with the right arm currently installed. Take a look at this photo.

http://ibexbikes.com/products/index.asp?product_key=16

Am I going to be out of luck without completely replacing the crankset?


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## jochribs (Nov 12, 2009)

The redlines should be 110 x 5 arm bolt circle and narrow wides are available. I think the smallest is 38t though.

Edit: just found this...36 t...figure should be able to go smaller, still room around bolts for smaller circumference, but 36 is the smallest I've seen so far. Maybe others/ smoking man have more knowledge.

Blackspire Snaggletooth Narrow Wide CX Chainring | Chain Reaction Cycles

Edit 2...34t...not sure if there's material left to go smaller after 34, unless someone has done a threaded ring like the 104 30t rings.

https://www.worldwidecyclery.com/pr...L4P8YTPAPRNgMmzmukB5ItVfvp8xg3yLRoxoCL47w_wcB


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## thesmokingman (Jan 17, 2009)

jochribs said:


> The redlines should be 110 x 5 arm bolt circle and narrow sides are available. I think the smallest is 38t though.
> 
> Edit: just found this...36 t...figure should be able to go smaller, still room around bolts for smaller circumference, but 36 is the smallest I've seen so far. Maybe others/ smoking man have more knowledge.
> 
> Blackspire Snaggletooth Narrow Wide CX Chainring | Chain Reaction Cycles


Whoa, that costs more than the crank itself. 110bcd is 34t smallest ring. These are more reasonable below or the Sugino rings.

SRAM Force/Rival/Apex 10 Speed Chainring > Components > Drivetrain > Chainrings & Spiders | Jenson USA



pste said:


> Hmm... the bolt holes on the right arm don't look compatible with the right arm currently installed. Take a look at this photo.
> 
> http://ibexbikes.com/products/index.asp?product_key=16
> 
> Am I going to be out of luck without completely replacing the crankset?


If your requirement is to re-use the existing rings, there's a bit of info needed first like the bcd and what size existing rings they are.


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## jochribs (Nov 12, 2009)

^Well it's a start. Figured I'd look for gear for the guy to see if there was anything out there as the last 5 arm 110 bc cranks I had were my 8spd XTR 952's...way back...

Edit...Is he planning on running single ring?? If so, that 15 dollar ring is going to cost more than 15 after you bashguard it etc. I'd rather have a narrow wide personally.


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## pste (Apr 13, 2017)

Ideally, I'd like to do a simple swap out on the arm and keep the 42/34/24 upfront. I happen to live on top of a pretty massive hill, and would be hesitant to give up that 24T ring and run a single ring. One of the reasons I want to do this is to hopefully modify the bike so that she can make it to the top. The big cranks are, I believe, the primary thing keeping her from being able to do it. I guess trading the 42 for a 38 wouldn't be bad though, as the big chain ring is rarely used right now.


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## thesmokingman (Jan 17, 2009)

pste said:


> Ideally, I'd like to do a simple swap out on the arm and keep the 42/34/24 upfront. I happen to live on top of a pretty massive hill, and would be hesitant to give up that 24T ring and run a single ring. One of the reasons I want to do this is to hopefully modify the bike so that she can make it to the top. The big cranks are, I believe, the primary thing keeping her from being able to do it. I guess trading the 42 for a 38 wouldn't be bad though, as the big chain ring is rarely used right now.


That's asking a lot for a child, not to mention managing a triple crank and shifting. If you must keep the triple, you won't find many 120mm triples as they don't really market that to kids. Your best bet is to cut your existing cranks down to size and tap them. Steve-xtc will be here any minute to walk you thru this. It's not technically hard, you just need some tools and a drill press, or have a machine shop do it for you.


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## jochribs (Nov 12, 2009)

Pste, if all you need are shorter cranks, you can definitely shorten the ones that come on that bike as an option. There's plenty of meat there to cut down to 135-140. That way you don't introduce needing to replace anything else

^...dangit, this was content I typed last night and then deleted since I didn't want to say to much without knowing your intent. Anyway, I was just typing something else, and lost the screen, so I hit restore content and it put this in instead of what I was just typing. My screens so small I didn't realize. Sorry it seems I'm just parroting Smokings post. 

Anyway, as a comparison, my son just came off a 20" that I customized cranks down to 120 for. He just moved to a 24" and I put 135's on. He's stoked. He is standing at 51" at the moment. Crank length seems just about spot on for him.


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## jochribs (Nov 12, 2009)

You will be surprised just how much better she will ride when her legs aren't forced to turn comparitively huge circles with the too long cranks. Seated spinning and standing pumping will all come more naturally. She'll clean that hill with a little practice.


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## thesmokingman (Jan 17, 2009)

jochribs said:


> ^Well it's a start. Figured I'd look for gear for the guy to see if there was anything out there as the last 5 arm 110 bc cranks I had were my 8spd XTR 952's...way back...
> 
> Edit...Is he planning on running single ring?? If so, that 15 dollar ring is going to cost more than 15 after you bashguard it etc. I'd rather have a narrow wide personally.


Scratches head... if that 15 dollar ring is going to cost more than 15 if you decide to use a bash which you don't need, won't the 75 dollar ring cost more as well? I don't understand the logic of this post.

BBG bashguards for cheap. For kids, its more to keep their clothes clean than to protect from rocks.

https://www.bbgbashguard.com/


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## jochribs (Nov 12, 2009)

Don't scratch too hard, you might bleed. 

The ring you posted is a ramped and pinned ring. With the intent of running it 1x. 

There might be other options out there that are cheaper, but Ill say, I've never been a fan of cobbling together any old crap just because it saved a few nickels. The point was looking to find PSTE a few options quickly for examples sake. 

Running single I'd never run a bash. Especially with narrow wides available. And keeping their clothes clean?? Ok. Not my thing. To each their own. 

Smoke up Johnny.


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## pste (Apr 13, 2017)

Thanks all. I think I will modify the arms as long as I can find a machine shop to do it. I may simply add a hole at 127mm and leave the additional length in place. I found out that Trek's kid's bikes actually come with two-hole cranks at 120/140mm or 127/152mm depending on the bike, and the additional length isn't a problem. (The Trek LBS in my area didn't believe that one of these custom crank arms could be slapped on to the Suntour cranks though...) 

For now, my daughter wants me to leave the cranks alone though. We'll see if I can convince her to want to try it. I'd prefer her to WANT the mod before actually doing it. I can tell it's hurting her cycling but she can't. Regardless, she's the oldest of 3, and I'll want them shorter before her little brother gets big enough for the bike.

(I mentioned that my hill was massive, but realize that's a relative term. It's about 100 yds long with a ~50 ft elevation gain, for around a 16-17% average incline. It's short enough that she could do it, but steep enough to make it quite a challenge.)


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## jochribs (Nov 12, 2009)

I'd just shorten the cranks pste. She'll benefit from it, unequivocally. If she doesn't get over it and forgive you, I've got some 152 4 arm cranks with a 32t ring and bash that you can have. But I think she'll see the light after she feels the difference.


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