I pulled the RD engine this weekend and disassembled everything. Of course it will get new bearings and seals, the crankshaft is still very good, as are the gearbox and clutch. But the clutch has to go, it’s a two plate model, i will try and fit a four plate clutch from a DT80.
There will be some machine work done to the crankcase, as i will fit a cylinder from a Minarelli scooter engine. The gasket surface needs to be lowered 2-3 mm, the bore for the cylinder skirts will be enlarged and the transfer ports need to be matched.