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11/17/13, 8:01 PM   #1
Compression readings?
RACEMAN
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What would be a good compression reading on a gauge for a healthy 07-08 R1? I got one coming to me and want to check it out before I decide to keep it for sure. Thanks in advance! Dave
 
11/17/13, 8:25 PM   #2
Re: Compression readings?
TQ29m
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A quick google says 190-210 psi, all plugs out, throttle wide open, engine cold. I'd do a leakdown, gives ya a better fix on things. Cranking speed on compression test. My 600R runs a tad higher, more compression, 13-1 on it, it runs 230+. Bob
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11/17/13, 9:59 PM   #3
Re: Compression readings?
badcoupe
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I would run a leakdown test on it, it will give you better idea of what kind of shape the motor is in. Either way your results need to be close for every cylinder, 15% is the typical guideline for variance between the highest and lowest readings. If you do a comp test make sure that the battery you use is charged well or on a charger so that the cranking speed is consistent for all 4 tests.
 
11/18/13, 1:07 AM   #4
Re: Compression readings?
DAD
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Quote:
Originally Posted by badcoupe View Post
I would run a leakdown test on it, it will give you better idea of what kind of shape the motor is in. Either way your results need to be close for every cylinder, 15% is the typical guideline for variance between the highest and lowest readings. If you do a comp test make sure that the battery you use is charged well or on a charger so that the cranking speed is consistent for all 4 tests.

Race


After these motors sit for any period of time without lube on valve seats the Ti valves tend to corrode and cause poor leak-down or comp. readings. As soon as motor runs a little this stuff clears up and your readings will go up.

I have taken wd-40 and removing valve cover and applying air to cylinder with the leak down tester and hit valve cup lightly with thin brass drift several dozen time and cleaned the faces this way. You will know if you are hitting it right it will make a pop-pop-pop sound as the air releases.

Honest Dad himself
 
11/19/13, 12:12 AM   #5
Re: Compression readings?
RACEMAN
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Thanks for info. guys! Raceman
 
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