1988 yz80 just got a new top end and gaskets, was bored up to a 90cc by millennium technologies, haven't broken it in yet, but how much psi should it be after broken in? It doesn't seem like it will gain much compression after breaking it in, I have a brand new ring and piston and bored/honed jug, right now before starting it up to break it in it feels low, really low compared to my 216cc ored blaster (broken in). Any suggestions or does an 80 naturally have pretty low compression compared to a doggish 200cc 2 stroke?

Its a smaller motor. Thats why it doesnt feel like its got a lot. Like an 85 will never be as hard to kick as a 500. And yes compression does go up slightly after break in because the rings will seal better to the cylinder

kb228 wrote:

Its a smaller motor. Thats ...more

kb228 wrote:

Its a smaller motor. Thats why it doesnt feel like its got a lot. Like an 85 will never be as hard to kick as a 500. And yes compression does go up slightly after break in because the rings will seal better to the cylinder

That's what I figured, thanks for the help