Hi I'm Joe and I have a venerable old 1993 Gas Gas Jordi Tarres replica Contact T-25 aka as a JT 25 or GT 250 sometimes depending which You tube video you watch,. the bike was bought as a wreck needing :-

New Suspension bearings, new clutch plates, the clutch slave cylinder screw threads needing Helicoiling, a clutch rod, CDI repairing, the plastics repairing, new water pump seal, a radiator fan switch of some kind, a fan motor rebuild new rear brake master cylinder

However apart from the clutch rod, and the original light units it was all present had good compression and the motor its self felt good.and so could be made good. . . . over some considerable time

Sounds like you’ve picked yourself quite a project. Good luck and let us know your progress.

It is pretty much done, I didn't find this forum till I started trying to find somewhere around the fens to ride it where I wouldn't get pulled by Plod. No success so far on that front. It's just niggley stuff now with the bike. The rectifier seems to have packed in this week so the fan won't now work even though it's fine and so is the thermoswitch. but that is the joy of old bikes ( this is my only old"ish" trials bike but I have a few old road bikes ) just when you think everything is sorted for summer there's another bit reaching the end of it's service life.