Ktm sxf 250 2011 Different fork springs

I believed spring calculator and bought 4.8 fork springs.

 

Setup atm

0.48 fork springs

5.4 rear spring

 

360ml oil height

105mm sag

30-35mm static

 

Problem is forks arent stiff, but even fork comp almost full open its not bottoming even at overjumping. There's still like 20mm room for movement.

Just thinking where did those MXA and race tech succestions came from to run so stiff fork springs?

 

I'm

185lbs without gear

6.2"

 

Can I run 0.48 on other fork and put 0.44 to other to achieve 0.46 spring rate total? I dont see any problem there, but I have read that's too much difference? Why?

 

And any other ideas?

Hmm... it doesn't sound like your far off. Have you tried measuring fork sag? It may give you a better picture of were your currently at. Usually the forks should sag around 60mm for the springs to be close. I bet in your case, the sag around 50mm or less.

So what's the solution? I like the .44 in one side and .48 in the other. Also, they do make .46 fork springs, those are the stock ones for the 2013+ 250SXF. Honestly, they're perfect for ya and if you needed it to be a tiny bit stiffer for whatever reason, you could do a .46 and .48 combo to = .47 which may be the perfect rate as your not too far off.

Edited by tye1138

well, cant remeber fork sag. I have measured it but it just very hard to measure correctly.

 

And 0.48 and 0.44 because got the 0.44 springs laying around.

Edited by jotukka

whats your oil level?

 

adjust your oil height.  While adding heavier springs, the oil level was raised by increased wire diameter of the spring.   making that change from .44's to .48's you should also have added reb damping internally with shims

 

 

wp tc forks oil range-   325-390ml  this influences the bottoming resistance

 

 

 

 

 

 

 

 

 

sent from mars

where did you find oil range? running atm 360ml mainly because I havent found oil level low limit. And stock is 380ml and didnt want to take risk of too low level.

 

Damping is stock and its working fine, actually adjusted clickers faster than stock.

Faster than std ? That seems odd to me

where did you find oil range? running atm 360ml mainly because I havent found oil level low limit. And stock is 380ml and didnt want to take risk of too low level.

360 - 380 is the range I'd consider "working". Much below that and your anti-bottoming will be reduced substantially. Of course, it does depend on the spring rates and type of riding, I'm assuming motocross due to the bike type. But I run similar rates and have found the optimal to be in that rage. Its nearly impossible to get the oil level perfect unless you strip the forks down to bare components. So it fluctuates on the high side of things for sure.

Damping is stock and its working fine, actually adjusted clickers faster than stock.

Actually, the compression stack should be OK, but the rebound stack is most likely not ok. You should need MORE rebound when you add stiffer springs.

Now forks are working much better. I adjusted rebound wayy slower and it was much better, wierd because bike was oversteering when riding at rut.

 

Anyway, is that 325ml wp low limit for oil? Thinking of lowering oil level from 360ml to 350 or even 340ml.

Try 325 if you want it does make a difference

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