Heavier fly wheel weight,exc piston,exc exhaust pipe an silencer and you will be all set for now.But eventually you will want some bark busters,pipe gaurd,and skid plate.Maybe even a larger tank.Yes the power valve is adjustable but it wont make it any smoother it will just delay the hit and then when it does hit it will hit harder.An exc piston should do the trick.You will need a PV tool from the hard parts catalog to adjust as far as I know.Hope this helps
