Motorcycle Repair: Rm80, piston kit, cylinder bore

Question
I am rebuilding my rm80 and i am just wondering if you have to
get the cylinder bored when you get a new piston kit..and if
not whats the difference?

Answer
The cylinder bore should be inspected for scratches or scores, if the bore is in good shape, the new piston with new rings may be fine, but usually you will have to go with a first oversize piston and the the bore machined and honed one oversize to make things 100%.  Good luck,  Jan