My 13 year old daughter is just getting into riding and has moved up from a Sherco 2 speed auto to an old 80 fantic air cooled mono which was the lads. He was happy to just tazz about on this, but I think she is going to want to compete. I've looked at other small bikes and they seem as useless as this one so, as I have a 125 engine I thought I would slot it in. I've seen some reports of people doing this years ago to create a useful schoolboy mount, but no technical detail. Can anyone remember if, they used the 80 or 125 exhaust and air box. Anything else that would be helpful??? 

If you contact Bill Pye at Frankfield Garage, Great Ayton on 1642 722378 he might be able to advise on how feasible this is. He's Mr Fantic, knows almost everything about them.