This is some of the evolution of my 1978 Yamaha XS500 over 35 years.This past summer I sold off all the 8 valve twin engine parts and bought a hammered up '92 Blaster just to get the engine out of it.I am in the process of a full engine rebuild with Hotrods stroker crank,Wiseco piston and outer clutch basket, my own porting,Barnett clutch springs,VForce4 reeds,my own intake manifold with a Mikuni TM36.My buddy is doing the bore and squishband head. Next up, motor mounts in the bike chassis.And some engine pictures........