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Compression comparison

lgpanther

lgpanther
Has anybody taking an old fashion compression test of their cylinders and compared it to the manual specs? Took a compression test on my R1200CL and got about 200psi on both cylinders, but the CD manual says normal is between 121 - 140psi. Just want to verify, I will not pop the head off.
 
yeah, a reading of 200 psi on that motor is indicative of one of 2 things- test done incorrectly, or an amazing amount of carbon build up on the piston top.
 
Any chance you're misreading the scale on the device? Often times there are multiple scales. Simetimes, pressure is measured in kilopascals. 200 kilopascals is about 30 psi. If you really set up the pressure test wrong - cold engine, carb slides completely closed, etc. - you could get an extremely low reading in psi but it might look high if you read 200 off the kilopascal scale.
 
I'm not much a fan of compression tests, other than it might indicate low compression (worn out engine) or high compression (high carbon buildup). But yes, a compression test must be done with the throttle wide open.

To me, a much better test is a LEAK DOWN TEST. A LTD will tell you "where" the issue is, not just what it is. any good competent mechanic can do the test.
 
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