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Spring rate for xr400 USD swap

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So I did a USD swap on my 2001 XR400 last year and it is amazing. I am thinking though that my springs are a little soft front and back. I have an idea of what i would need for my rear spring (~11 kg/mm), but i don't really know where to go for the front. The forks were revalved by TBT racing and are setup for woods riding (like i said, they are really nice), but i think the fork springs are little soft. The thing is, the online calculators are taking into account the cr250 weight, not my tank of an xr400. hahaha. I ride anywhere from single track to highspeed woods roads. Could you help steer me in the right direction?


Rider weight: 225

forks: 2001 Showa cr250 -springs right now are .44 kg/mm

I think the xr4 weighs around 265-270.



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Forks are one to one so fork springs are close even for different brands. 0.48 kg/mm would be my choice. You could go 0.47 or 0.49 for a soft/stiff option. any one of the three would work. They should match the rear at 11 kg/mm. the XR weighs 277 wet with one gallon.

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