I'm doing a shock oil change on a '05 CR250. This is the 1st time it's ever been cracked open. 1st thing I notice w/ spring removed is that the shock didn't retract fully after compression. It would stop retracting about 1/8" before end of travel. THe other issue, I'm seeing quite a lot of air bubbles mixed in w/ the dirty fluid. There's no leaks that I can see. And the bladder has no holes and it held the air pressure fine. My question is what caused all the cavitation?