I never thought I’d have to worry about a vintage 2 stroke having too much compression but is 190 without exhausts on too high. If so what would be the cause and solution?
I checked the compression tester on a few other things and it seems pretty accurate. Do you think the head gasket could be so deteriorated that the cylinder is sliding down and that maybe there is a lot of carbon build up on the head?🤷♂️
Yes, good idea . . . wouldn't hurt to pull the head and clean it if it is indeed carboned up, but bottom line is . . .
If the bike is running well, don't worry so much about your seemly high compression reading. Yamaha never gave compression specifications in their service manuals, so I don't think you should make too much of it if the bike is running well.
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Awesome,thanks as usual. 👍
Thanks for posting your concern, .... but It's highly unlikely your compression is that high.
In fact, 190 psi would be virtually impossible to achieve even if you were trying.
Is this your 360 you're talking about?
From experience, 120 to 135 is more the norm for a good healthy running engine.
Perhaps the gauge you are using is faulty
I'd suggest trying a few more gauges and compare your results, as things just don't add up.
If the bike has been running fine, I probably wouldn't worry about it.