how do u rebuild the top end on a blaster and shave the head..do u have to shave the cylinder wall at all..and will a stock piston and rings still work if i shave the walls

 

Shave the walls? You mean bore it out right? In that case, no, you will need a larger size piston based on how far you bore it out. What octane gas are you running it on? .030 is the limit for pump gas or else you'll be knocking like crazy.