Thanks, that gives me an idea. I'm having a set of heads done. With the stock 69cc volume and the head gasket volume, I will be at least 9.4:1 on compression. They have been milled in the past but I haven't measured how much. It will be close to the upper limit for pump gas.


Lawrenceville, GA

Does anyone have any idea how much volume is gained after polishing the combustion chamber of a g-head?


Lawrenceville, GA