You're looking at the blue-anodized high-speed compression adjuster with the straight-slot low-speed compression adjuster. Virtually all the parts that will be changed are inside the shock, with the exception of the coil spring. The urethane bumper might need replacing as well; mine was pretty crusty.
The coil that came on my '00 125 was a progressively-wound coil that went from too-stiff to way-too-stiff. The shock linkage alone makes the spring rate rise as the shock gets deeper into its travel, so a progressively-wound coil on top of a progressive linkage results in a rear suspension that kicks hard and kicks often.
I recently took my rear shock to Too Tech Racing. On top of swapping out the coil for a straight-rate style, there were quite a few changes made to the shim stacks and to the compression adjuster assembly. There was also an internal stop washer that was restricting high-speed oil flow, so it was turned down on a lathe to allow better oil flow. Combined, these mods have made a night-and-day difference.
Too Tech is in Torrance, so it should be convenient to take your shock in to get work done. The owner's name is Rick Johnson and he's friendly and easy to work with.
Basically, you want to tell Rick your height, weight, ability level, and your intended use for the bike. He will take it from there and make the necessary changes. If the shock needs some re-tuning after the first re-valve, he will take care of that at no extra charge. He also keeps your specs on his computer for fast reference when you call with questions or send the parts back for maintenance.
Finally, while it's ideal to have both the shocks and forks worked on at the same time, Rick will modify one at a time if you need to go that route. If you only have one end done first, go with the shock.
I asked a lot of questions and took notes while I was there. Can you tell?
www.tootechracing.com(310) 371-3887
