Did a compression test today got 150 PSI +- 3 PSI on both cylinders after adding oil to the cylinder got 7 PSI higher. Am I looking at piston/rings issues or valve issues?
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Nothing will perfect. Unless it's right after a completed rebuild in a brand new engine. I looked around for a few minutes. 192 psi. With a tolerance of 28. So 150 isn't far off.
Search here and you'll find instructions. Other people with similar results. So I wouldn't work about it.
Ride it more and worry about it less.1988 Honda Hawk
2009 Yamaha TMAX
North Georgia
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You should be fine at 150. If you want to find out where you are leaking from do a leak down test. Fill the cylinder with air @ TDC, listen for where its coming out. That will let you know rings or valves.
But unless its down on power or smoking, i'd keep riding it.Don't spend money and buy, spend time and learn.
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numbers seem good, especially for the piston rings.of course you held the throttle wide open ? engine hot or cold ?
Last edited by squirrelman; 10-09-2021, 08:08 PM."It's only getting worse."
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150 isn't terrible. Certainly not worth tearing the lump apart. Generally if you add a bit of oil into the cylinder and get a jump in compression that points to the rings, but again, I don't think you're at the new rings stage yet. I wouldn't worry until you see something like this:ASMA #139
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