Well i took the cluch cover off today, cleaned the friction plates, bead blasted the steels and put it back together with fresh oil and now the clutch and gears work properly but the damn thing misses pretty badly. The plug is a B8HS which is a new one the owner put in but i have no idea if thats the right one for it. Ive been right through the carby the otherday as it was full of crap and fitted a new main jet but couldnt get the short mikuni hex and had to go with the long hex but i dont think thats a problem. What sort of points gap should this have? i was thinking 0.30-0.40mm as thats what some specs for some later 50cc yams said.
By the way the barrell says U5 on it so its definitely that model.