I just did a compression test on my 2012 pro rmk 800, got 120psi in both sides, warmed up sled first plug in opposite side and i am at 700ft above sea level, sled has 2100mi, what are the factory specs? Should i be thinking of doing the top end and if so what is the best kit? Thinking BMP, Thanks for any info.
2012 pro rmk 800 compression test
- Thread starter imrede73
- Start date
Compression test
I was taught to test a two stroke engine by taking out the spark plugs
Then screwing in the tester while leaving the one
Cylinder without the plug in then pulling the engine
Over on a cold engine . Maybe someone who builds
Engines for a living can chime in here and tell all how the
Correct way to do a compression test.
I was taught to test a two stroke engine by taking out the spark plugs
Then screwing in the tester while leaving the one
Cylinder without the plug in then pulling the engine
Over on a cold engine . Maybe someone who builds
Engines for a living can chime in here and tell all how the
Correct way to do a compression test.
The book doesnt show compression specs, it onlys says the compression numbers be within 10% of each other. 120 psi is still a respectable number
there is no spec for compression by any manufacturer of engines , the only ones i have ever seen is on diesels , compression numbers vary wildly depending on altitude in my opinion 120 is great compression .
that being said any 11 or 12 800 needs a fix kit and have cylinders inspected for cracking. i had a 12 i pulled down to do a fix kit that had only 60 hrs on it that had severe skirt cracking. so beware 400 bucks to repair now or a couple of grand latter. 13 and up are much much better durability wise.
that being said any 11 or 12 800 needs a fix kit and have cylinders inspected for cracking. i had a 12 i pulled down to do a fix kit that had only 60 hrs on it that had severe skirt cracking. so beware 400 bucks to repair now or a couple of grand latter. 13 and up are much much better durability wise.
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Test it cold, both spark plugs removed, throttle held wide open, 5-6 full pulls or until it no longer builds anymore pressure.
Gauges vary too much to know if 120 is good or not. As mentioned, the main thing is that they are equal.
I can tell you that my 12 and 14 pros tested at 105psi at 6200 ft. 3% loss for every 1000ft increase in altitude. So 105 + 18% = 124 psi at sea level.
These engines do have lower then average compression, even in 100% good condition. Eric
Gauges vary too much to know if 120 is good or not. As mentioned, the main thing is that they are equal.
I can tell you that my 12 and 14 pros tested at 105psi at 6200 ft. 3% loss for every 1000ft increase in altitude. So 105 + 18% = 124 psi at sea level.
These engines do have lower then average compression, even in 100% good condition. Eric
X2 on mtncat1's Reply. My '12 had 1900 miles, ran great. Decided to install a durability kit as precaution. Upon tear down found cylinder skirt cracking. I was just happy I caught it before it came apart!!
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