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4CS revalve offroad for revalve newb

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Ok, this is long over due. I can fix, repair, etc everything else on these bikes but never revalved on my own. I have rebuilt several forks and shocks in the past. I want to learn this secret black art. I have a basic understanding as to how valving controls the fluid movement, but I don't get the whole shim stack design or how some of you gurus can just looking at stack configuration and predict the riding characteristics.

So my starting point is a 2015 KTM 250SX that I am setting up for desert/offroad. I know what the bulk of the opinions are on this fork and its reputation. It does beat me up pretty good offroad, but it could have a lot to do with the SX valving. It is sprung for my weight, and when the time comes to open it up I want to do the Terry Hays mods which seem to work well for a lot of folks. As well as the compression bases. Same goes for the shock, XC setup and go.

Outside of someone telling me their secret formula, is there a valving database out there? Worst case is I may just look for stock 15 XC valving and start there as my baseline. More offroad friendly and I can tune/experiment from there.

So from here any suggestions? Do I even bother with Mimicing the XC setup? How do I even start moving shims around? I don't mind the work and hope to learn a lot and get some experience in this area.

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There are some good posts on here but there are plenty over at Ktmtalk.com

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On KTMtalk Your looking for a post started Terry Hay.  Called 4CS fixes or something like that.

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Step one of your journey,  I would just put a 16.2 restrictor shim on top of the basevalve, that is very cheap and good way to get started. This is the single most important

step in "fixing" the fork. You can throw whatever shim stack you want in there but nothing helps more that restricing the size of the ports on the  base valve thereby

increasing the pressure flow on the shim stack so it actually does something in a firm progressive manner. I have also had very good succes removing the cartridge

seal (open chamber) but valving must then be upped on all fronts Base, Mid and rebound.

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