14' KTM 300XC Shock Help

Wundah · Jan 21, 2015

So the winter started out slow but it's finally feeling good up in the hills where I am on the Eastern Slopes of the Cascades but what I'm finding out so far is I need to beef up the front shocks on my bike. MtnDoo built this baby and she rips, Ultimate 300 in my shop and I love it. That said Ultimate was all in the motor and on my last ride I was bottoming out the front end more then I'd like. Any quick fixes for the 4CS system you guys can recommend?

mxracer299 · Jan 22, 2015

Drop in some .54 springs, that will help a lot. After that you can revalve it if need be.

TillTheEnd · Jan 22, 2015

Unfortunately there no quick fixes for any fork set up. I'm at 2 sizes over summer spring size, I'm thinking I'll end up 4-6 sizes to balance this thing out. But also the XC valve specs are light as well Im going to drop in something similar to a supercross spec valve stack and see what that does. But first I'm waiting on some old OC forks I bought to show up. I think a rider almost needs 2 sets of forks one summer and one winter. Or call RG3 in Idaho there's some guys on here real happy with there work for snowbike valving

NorWest Suspension · Jan 22, 2015

Wundah said:
I was bottoming out the front end more then I'd like. Any quick fixes for the 4CS system you guys can recommend?

Hi,

What is your weight without gear?

Stiffer springs are the first step and then move on to the valving.

There are several areas that can be improved on the 4CS fork, One issue is the damper shaft diameter to piston diameter ratio is not correct in stock form and it takes a very stiff shim stack to get the compression where it should be. Racetech came up with a solution that uses smaller OD shims and has less port flow area compared to the stock valve. Another is the flow are of the stock mid-valve as it is restrictive and creates a very progressive curve in stock form. That is two issues but there a couple more as well.

Terry

mxracer299 · Jan 22, 2015

Springs are only part of the problem, you need to valve it to work really good but some people can get by with just springs. I would highly recommend having 2 sets of forks, not only will the snowbike setup not work on dirt, if you wreck your forks which is very possible you are out a bunch of money. I got a set of closed chamber forks off of an 08 450SX and dropped in .62 springs and I still bottom them.... but if I wreck them I'm only out 3-$400 instead of 2-$3,000. The older closed chamber sx forks work pretty good on snow though, they are about 1 1/2" shorter which really makes it turn better and the valving is quite a bit stiffer!

chumbilly1 · Jan 22, 2015

mxracer299 said:
Springs are only part of the problem, you need to valve it to work really good but some people can get by with just springs. I would highly recommend having 2 sets of forks, not only will the snowbike setup not work on dirt, if you wreck your forks which is very possible you are out a bunch of money. I got a set of closed chamber forks off of an 08 450SX and dropped in .62 springs and I still bottom them.... but if I wreck them I'm only out 3-$400 instead of 2-$3,000. The older closed chamber sx forks work pretty good on snow though, they are about 1 1/2" shorter which really makes it turn better and the valving is quite a bit stiffer!

Are you sure about the 1 1/2" shorter part. I really doubt it. The only year that was shorter was 07 and they were like a few mm shorter, but still noticeable.

Steve, Go on ebay and buy a set of old OC cheap forks from an sx. Then get stiff springs and heavy oil. If you stiffen up those 4cs for snow, they will not work well for youin the summer!

NorWest Suspension · Jan 22, 2015

chumbilly1 said:
If you stiffen up those 4cs for snow, they will not work well for youin the summer!

Why not just have springs and a different shim stack(s) set aside for summer and just swap them when you switch back and forth?

Terry

madmax · Jan 23, 2015

NorWest Suspension said:
Why not just have springs and a different shim stack(s) set aside for summer and just swap them when you switch back and forth?

Terry

You could also do that if you want. Most guys don't know how to pull their forks apart and change out the shock parts. A second set for winter is a great idea if you can find an affordable set. Not good for your forms to be bottoming out all the time.

NorWest Suspension · Jan 23, 2015

On another note, The 4CS only shows 7mm of chrome at bottom out and when installing the clamp (TS clamp) on the fork tubes it is roughly 19mm thick and then usually raised another 4mm to clear the tab and you are going to bottom out on the clamp before bottoming out internally in the fork. So in essence you lost 17mm of travel.

Terry

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14' KTM 300XC Shock Help

Wundah

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TillTheEnd

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NorWest Suspension

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chumbilly1

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madmax

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