BannedCR500Riders.com

Putting together a new to me 2000 CR500R. Engine is stock. Wiseco 89.50 piston, stock gaskets. I measured the squish and came up with what seems like a massive ~0.100" clearance next to the cylinder wall. The "lip" on the head all by itself is ~0.075" deep.

I wanted to use solder in the hopes of getting easier to measure results, but my rosin core solder is only .062" thick. So I used clay. This may have introduced some measurement error on my part but I'm confident 0.100" is close to actual.

I was thinking about half that clearance would be better. What say you?

I have never measured mine but I was told by GSS that the squish on my motor should be around 45 tho (race gas only).

measure that again. .100 doesnt seem right

Clay dosent lie.... look's like 0.100 to me.

.070 was taken off my head. Looks like .020-.030 left.

Theres no "base nuts" in the photos. You sure the jug didnt pick up while you were turning the motor over?

100hp honda wrote:measure that again. .100 doesnt seem right

I agree it seems excessive. But if it's not .100" it I'll be damned. The head itself has .075" of relief. Add in a head gasket, some deck height, and a smidge +/- for measurement error and there ya go: .100".

AlisoBob wrote:Theres no "base nuts" in the photos. You sure the jug didnt pick up while you were turning the motor over?

Good eye! But yes, the nuts were installed and torqued when I took the measurement. That pic was right after I got the jug down.

Stock on most cr500 was about .100 to .140.

I had 50 off mine, no probs, but race gas only...