# Rear shock options.



## Swissam (Apr 8, 2008)

So I just bought a second hand Scott Nitrous Jr. 20" fully for my son.
I already plan on upgrading the fork to either the spinner 20" air or the RST f1rst 20-24" air. Which brings me to the shock. Where can I find a decent air shock for such a bike? I know they exist cause I've seen them on bikes from Lilshredder and Propain however I don't want to spend over 1k just yet. Although I will eventually. So where can one buy?
Many thanks for any info. Rep points will be rewarded


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## Swissam (Apr 8, 2008)

Sorry but I cant help myself. So proud of my little boy and his new (to him) rig. I have a scott gambler so it seems fitting.


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## griffter18 (Jul 3, 2009)

Youll probabley struggle as the rear shock is much more complicated than a fork as its limited in terms of compression and extension.
The later Spark had an upgrade option to air but they were very limited and are no longer made.
You may be able to get a short shock modified but it wont be cheap.
There was a post on here were someone had a scott nitrus and was looking at the same issue. Cant recall if they found an alternative


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## slapheadmofo (Jun 9, 2006)

What is the eye-to-eye and required stroke for the shock?


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## Swissam (Apr 8, 2008)

slapheadmofo said:


> What is the eye-to-eye and required stroke for the shock?


Not sure yet, I pick it up on Friday. 
Looking at getting a spinner air 20 or a RST first air 20 fork. 
Then replace (hopefully) the shock. Maybe seatpost, stem and bars to reduce weight and I already bought two new schwalbe black jack tires. This more fun than upgrading my own bike. Lol


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## griffter18 (Jul 3, 2009)

Found the thread Id seen it on.
The shock that was used was a KS A5 RR1 rear shock.
The thread is located on another forum (hope this doesnt break the rules):Anyone's kids have a Scott Spark JR 20 or 24? « Singletrack Forum
There a similar thread on here where member discusses option available for a spark and it looks like the eye to eye is the same see post#3 in the following link.
http://forums.mtbr.com/families-riding-kids/new-scott-spark-jr-20-modifications-796870-3.html

The KS is a very basic shock so dont expect too much from it, the Xfusion is the better one but is obsolete.

As posted earlier you may be able to get someone to modify a shock as well if you can find somethng close.

Hope this helps


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## griffter18 (Jul 3, 2009)

Swissam said:


> Not sure yet, I pick it up on Friday.
> Looking at getting a spinner air 20 or a RST first air 20 fork.
> Then replace (hopefully) the shock. Maybe seatpost, stem and bars to reduce weight and I already bought two new schwalbe black jack tires. This more fun than upgrading my own bike. Lol


haha yes it can be quite addictive but very satisfying.
From my own experience go with the RST F!RST 20 or 24 fork as this offers rebound and compression setting compared to Spinner. You'll also be able to get it serviced much easier as there doesn't appear to be many places that deal with spinner so parts can be a problem.

go with 20" if you plan on keeping current brakes,
go with 24" if you plan on switching to a 24 frame at a later date or adding discs.You can get an adaptor to fit current brakes to a 24 if you need and it will give a slightly slacker head angle.

The rest of it is down to finding the right components at the right price and is good fun.

Rear shock is potentially going to be your biggest problem though.


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## Swissam (Apr 8, 2008)

griffter18 said:


> haha yes it can be quite addictive but very satisfying.
> From my own experience go with the RST F!RST 20 or 24 fork as this offers rebound and compression setting compared to Spinner. You'll also be able to get it serviced much easier as there doesn't appear to be many places that deal with spinner so parts can be a problem.
> 
> go with 20" if you plan on keeping current brakes,
> ...


Thanks for all the info and links, really helpful reading. The A5 shock looks good enough, it's not like he needs a RC4. Regarding the RST fork, I can't find the 20" so I'll go with the 24" with the slightly slacker geo which is a good thing as even some of the easy trails in the Alps have some steep bits. Now I just need to find the adapter for the v-brakes or look for new wheels to accept disk brakes. I have an extra pair of Elixer 5's in my parts bin, just need the wheels and smaller disks. Are disk brakes even needed for a kids bike? I would think v brakes would be easier to learn without the risk of going OTB. Anyways it really hard to keep my trigger finger in check. First I need to pick the bike up and take some measurements before I start rapid fire ordering. Lol

Link for the rear shock
Bike Rear Shock - Shop Cheap Bike Rear Shock from China Bike Rear Shock Suppliers at Oriental Cycle Parts Warehouse on Aliexpress.com

I'll have to contact him with a proper eye to eye measurement and see what fits. His shock says 150mm but judging from the pics there is no way that thing is 150mm unless he means eye to eye and not the stroke.


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## slapheadmofo (Jun 9, 2006)

griffter18 said:


> Found the thread Id seen it on.
> The shock that was used was a KS A5 RR1 rear shock.
> The thread is located on another forum (hope this doesnt break the rules):Anyone's kids have a Scott Spark JR 20 or 24? « Singletrack Forum
> There a similar thread on here where member discusses option available for a spark and it looks like the eye to eye is the same see post#3 in the following link.
> ...


Good find.

125mm eye to eye is definitely not common.
Depending what's on it, the KS shock might be an improvement. Then again, it might not.

Aliexpress.com : Buy KS Kindshock A5 RR1 RE 125 150mm Rear Shocks for Downhill road Bike Mountain Bicycle mtb free shipping from Reliable bicycle trunk suppliers on Super Goods Shop | Alibaba Group


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## griffter18 (Jul 3, 2009)

If you click through the link youve provided you will eventually get the info you wanted.
The A5 on the site is 150mm eye to eye and has 30mm stroke.

If you go with yhe 24" fork youll need an adaptor for your brakes. Do a search if the forum as a couple of member have already done this. Think it was on o hotrock.

Always have to keep an eye on the build cost as they quickley mount up. Good fun though.

Dont mention disc brake though as its a hotly debated topic in respect of safety.
Personally ive fitted discs to both 16" and 20" and as long as you teach your kids the dangers. all depends on what your riding and how much stremgth the kid has to operate traditional brakes. Id rather the kid could stop.


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## Will Fisher (May 12, 2015)

Guys, I just put one if those KS A5 RR1 shocks (the one with the main chamber and negative chamber) on my son's Spark 20 and I'm wondering if you have any tips as to correct air pressure. He weighs about 50.


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## the-one1 (Aug 2, 2008)

As with all air shocks/forks, set the air pressure based on sag.


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## Will Fisher (May 12, 2015)

Thanks the-one1 but what about the negative?


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