because of the dismal performance in the whoops I decided to go back to the OHV park and try some suspension tweaks. I played around with the rebound rate (the only thing besides the preload and charge pressure that is adjustable) and my lap times were identical (over aprox 5 mile test course) and it felt the same... hmm, I tried the same thing with the front forks by changing the oil weight in the past, and I a small change usually makes a significant change in the track time.
anyway, at home, I took off the shock and checked it, and it looks like it doesn't have any charge, and it sounds like it has some air in the oil, also there is some oil on the shaft, so I think it's blown. also, the adjuster knob is cracked, so it won't really adjust anything, anyway.
did some research, I can send the shock in to a suspension place for a rebuild $200-300, or maybe a rebuild plus a emulator/cartridge upgrade $300-600, or a new after market shock from works performance, between $700-1000... sigh. haven't seen any shocks for this bike (1981-1983 XR200R) on ebay, besides they are likely to have dried seals or worn after 30 years as well... checked my supply of shocks, and I have nothing that fits this bike, only bigger XR bikes.
hmmm. $1000 for new shocks, $300-400 for fork emulators, $200-1000 for a cam/stroker upgrade... it would be a pretty hot bike..., but still a xr200r. at the minimum, it would be nice to get it back to it's factory fresh glory.