valve for rebound ... = http://www.dreamgate.ne.jp/nsr/technical/fork12.jpg ???

That is what is known as your base valve (at the base of the forks). On these type of forks, it handles your compression valving adjustment. If you unscrew the bolt from the bottom piece in the picture, the valve will come off. You will have the valve and a stack of shims, a spacer, and a small spring. Carefully separate all these in the exact order they are stacked. The top side of the valve has the check plate and spring that opens to allow fluid refill on rebound, but does nothing for the rebound damping. The other side of the valve is your compression damping shimstack.

If you want some better valving specs, I can help you build the stack a bit better. I can at least set you up with the stock RS shimstack setup they used in the RS with 41mm conventional forks.

The rebound valve is attached to the bottom of the rod that attaches to the fork cap and extends inside the cartridge. You shouldnt have to touch this, the rebound is valved just fine on this bike.
_________________
Paul Herr
'88 FZR4/GSXR/YZF Frankenbike
MY BIKE PICS