compression test question

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bws2
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compression test question

Post by bws2 »

I did a compression check on my KDX200 and it came out to 175psi.

I didn't warm up the bike before I started, so it was a cold test.

Also, on my tester itself, the part that screws into the spark plug hole is much shorter than the length of threads on the spark plug itself.
Could the the test results be skewed if it doesn't thread in as deep as the spark plug?
Vossman
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Re: compression test question

Post by Vossman »

As long as the tester was screwed in good I don’t think so. 175 cold is good.
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bufftester
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Re: compression test question

Post by bufftester »

As long as the tester is not leaking around it then you're fine. As said, 175 is good
bws2
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Re: compression test question

Post by bws2 »

Thank you, Vossman and Bufftester
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G22inSC
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Re: compression test question

Post by G22inSC »

I have always heard that the length of the tester (ie threads) can skew the results but the secret to compression testing is consistency. You can't really look for any magic number as there are WAY too many variables. The key is always doing it the same way (hot or cold, same tester, etc.) and looking for percentage drops in the result. Just keep a log of your results and compare over time.
'05 Kaw KDX200 ('00 KX125 forks / '02 RM125 Showa "K2" shock)
'14 Yam YZ125(x) (oldest boy's)
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