Hey Phil, seeing as this was written a long time ago I presume you´d have the answer to this problem? Just picked up the same 74 model 100cc TS the other day... It´s in rough, rough nick but I managed to get it going, only problem is the Revs shoot up when I try to start it, Could be something sticking as of it´s age or could need carby adjusted so will get around to that soon. Let me know if you have a fix? Cheers Rob.