Well I pulled apart the forks on the 1984 Honda ATC 200ES Big Red to find that the fork dampers were shot. I looked to see if I could get some new ones but unfortunately found that they have been discontinued. This atc does not use what I would call a traditional fork where the inside of the lower leg of the fork contains oil. This style is dry where there is just a spring and a damper in the lower leg. The damper is a sealed “non –rebuildable” type. The damper contains oil and it is designed to dampen the oscillations from the fork spring. Since I cannot obtain a new damper and cannot find a good used one on eBay I decided to rebuild the ones I have that are pooched. What I mean by that is the damper has no oil left in it and it is doing nothing to dampen the fork spring. (If you compress the dampener it has no resistance and just bottoms out and stays there). What I did was simple I just drilled and tapped the dampener on the top mount to install a setscrew. I used a fork oil level gauge to fill the damper with 10W fork oil and then sealed up the hole with a pipe plug. I had to play around to get the right amount of oil in the damper so that it would do almost full travel with good resistance. This is not the best repair but the damper is not designed to be rebuildable (seal and rod replacement) but just putting some oil in made it a lot better than what it used to be. See pics and captions below for more details.
Fork damper disassembled
This is what I used to inject the fork oil into the damper
10W fork oil was used.
Hole drilled in top of damper
Tapped hole 1/4"-20
Oil was injected and setscrew with Teflon tape was installed
Damper assembled. I found that I did not need a spring compressor to install the spring on the damper.