I have a shock that came with a stumpjumper back when they were still Chromoly. I think it is the FSX with air and oil. First, can anyone cofirm that it is the FSX Future shock? The bike has the tange-prestige tubing and I think it is from around '92. I was told that the fork is just the Specialized version of the old Rockshox Quadra (???). Second, the shock seems OK but I have heard there are modifications to make it more plush and with more travel. It looks like someone drilled holes in the bottom for damping--actually, it looks like it might have been built that way. Is there anything else I can do? Can I still get seals and whatever else I'd need to do this? Finally, I realize it makes more sense to just buy a newer/"better" shock but I like the cool value of this old-school setup. Plus, it is a chance to mess around with the innards of my bike.
Dredging back through my memories of the earlier Specialized forks, I think the ones you have are either modified Rockshox Mag 10`s or Mag 21`s. Specialized used to buy them in from Rockshox (I think as more or less standard models) and change certain internal components. My experience (I work for a main Specialized dealer in the UK) is that Specialized used to be most obliging in terms of spare parts and technical support. As far as documentation goes, if you can get hold of the Mag 10 / Mag 21 service manual (Rockshox may still supply it - failing that, find a friendly bike-shop who still have a copy). As a rule, the two main things that will wear with time and normal use are the bushings and the seals. If you`re experiencing pressure loss (and commonly oil leakage at the top of the lower leg seals) then try removing and thoroughly cleaning the seals and stanchions, lubricate them up with some fork oil (Dextron ATF) and reassemble. If you find that there`s fore-aft play when the front brake is applied and the bike is rocked (not unlike a loose or worn headset) then it`s time to replace the bushings. These are buried way down in the lower legs, and there was a special tool that Rockshox supplied to dealers to prise them out without wrecking the cast lower-leg assemblies. You might (I know nothing about motorbike forks) be able to get a motor-cycle shop to remove the old bushings if your local bike-shop doesn`t have the tool. The replacement white-metal bushings were tapped into place with a phallic-looking lump of turned brass (also a Rockshox tool). Whilst you have the forks apart, check to make sure that there`s no scoring or corrosion-pitting on the upper legs - if there is, you`re doomed unless you can find a replacement set of upper legs. They could be replaced individually by means of loosening the bolts in the crown - correct re-tightening is such that the slot between the main bit of the crown and the bit that wraps around the upper leg is parallel - my trick used to be to slide a credit-card into the gap, and adjust until it was a smooth sliding fit corner-wise in the gap).
