uranys, on 06 July 2012 - 06:30 AM, said:
Lets look at some numbers....
A crf250r weighs about 100lbs less than a xr650l
The stock spring rate on most crf250r's is .45kg/mm which according to race-tech's spring calculator is good for a 175lb amateur trail rider.
If you put in 275lbs for rider weight (to make up for the xrl's extra 100lbs) it recommends .52kg/mm
the general feeling is that their calculator is a little on the stiff side so .48kg/mm-.50kg/mm would probably be appropriate for a 175lb rider on an xrl.
Yes, in general springs for mx are heavier, but not that much.
The valving is another issue, mx valving is tuned for big hits and will typically be too harsh for trail riding, even with the right spring rate.
Unless the forks you got were tuned for a 320lb trail rider, i can't see how they aren't undersprung and over-valved for your riding.
That being said, If your happy with them then great! ride it and have fun.
Racetechs calculater is WAYYYYYYYYYYYY off. All the others say .47-.49 for 240lbs. And that is off road riding, if you are casual, dual sporter, type rider, softer than that is just fine. Those would be WAY stiff for a 175 rider.
You can talk all the theory you want about valving and such, and I understand what you are saying and THOUGHT that would be a factor.
Thought I would have to have them resprung and maybe if you are trying to race that would be true, but for me, dual sporting and road riding, they are AWESOME,,,,,,,,,,,,, as is.