by GMP » Tue Jan 07, 2014 1:08 pm
Leon,
The 4stroke is a different animal, more weight and compression braking on top of that. Usually you find stiffer single stage stacks. The stock midvalve I listed is pretty tame, float is .75mm. The fork is awesome on everything but big whoops and landings. NO deflection, just a firm controlled ride. So the trick is getting a little more support out of it without screwing up the good manners. FWIW, on my GG I had the same float, no bleed, but two 20 x .15 face shims so that is like six 20 x .1s compared to the four on the Beta and it was still very good in the rocks.
You can get a CC fork to cavitate if the mid/base balance is off, that is the mid is stiff and base light. Oil being displaced by the damper rod flows through the base, remainder through the mid. If the mid can't handle it, extra gets pushed through the base and there is a cavitation on the rebound side of the piston if the pressure is low enough. The fork then feels like crap. You have to address both. This is not a problem on this fork, I think one reason why all the bleed, and the SKF seals, is to get a compliant ride on the trail trash from a CC fork, and getting the front end to bite.
If you have no luck getting stock specs, you could look to a well tuned KYB SSS used on say a WR450 as a place to start, as the forks share the same cartridge and rod dimmensions. I'm sure the pistons are different but probably not that different, and the pressure is lower. May be better than a wild guess.
Glenn
'13 Beta 300RR Racing