Did a compression check on the old BB drag bike last night, and wondered if these sound like good numbers:
Cyl. #1,2 & 4 190 psi. Cyl. #3 175 psi
This was done with throttle wide open, the engine stone cold, but cranked it enough that I'm sure the oil jets were squirting the cylinder walls. Figured that out when doing #4. The pressure shot up, so I went back and did the other 3 again. All 3 went up 20-25 more psi.
Motor is not stock. 81mm Wiseco pistons with valve pockets machined about .030" (didn't need to though). Machined .020" off the block, .004" off the head, and use a .018" head gasket. Stock head with stock cams and stock valves that the seats were re-ground. I'm sure I have at least 500 passes on it since this work was done. Spark plugs were all a nice light grey color. I have not done a leak-down test yet, but I'm not sure I need to.
I'm looking at building something different, so don't want to put any money into it, if I don't have to.
Should I just put some new plugs in it and race her another year?