Well, Thanks to keith Beasly of Standen Engineering, the mystery of why My new Bonded , rotor clutch disc would not work, has been solved! as indicated by another member Series ! Gem Rotor clutches had no linings at all, and the splined clutch plate (part no G610) operated “Dry” when the “Gem” mark 2 was introduced a new clutch plate (Partno G606) was introduced THAT HAD TWO RECESSES MACHINED on it, so only half the thickness of the new clutch fibre discs(Part no G607) would be in action, I had my original clutch disc bonded and this made the assembly too long, so therefore the whole roture locked up solid, I have now painstakingly chipped off the lovely new bonded linings and will try running it dry, the alternative, would be to machine the recesses in the existing plate or swop it for a later series 2 plate, AH well, at least I know what the problem was!