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Link works. just shows up different
 

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Problem is there is ZERO accurate way to test it. Go borrow 10 gages. Is the lowest right? Is the highest right? Or all the rest average them out? There is no such thing as a certified gage. Most important, don,t say my , example, snap-on because it’s big bucks is accurate. And don’t assume Amazon one is correct or a pos. Pick one, and look for a drop or difference hole to hole. If 100 of you swear by your gage, who says your right, thoughts?
 

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Problem is there is ZERO accurate way to test it. Go borrow 10 gages. Is the lowest right? Is the highest right? Or all the rest average them out? There is no such thing as a certified gage. Most important, don,t say my , example, snap-on because it’s big bucks is accurate. And don’t assume Amazon one is correct or a pos. Pick one, and look for a drop or difference hole to hole. If 100 of you swear by your gage, who says your right, thoughts?
 

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652 Posts
Problem is there is ZERO accurate way to test it. Go borrow 10 gages. Is the lowest right? Is the highest right? Or all the rest average them out? There is no such thing as a certified gage. Most important, don,t say my , example, snap-on because it’s big bucks is accurate. And don’t assume Amazon one is correct or a pos. Pick one, and look for a drop or difference hole to hole. If 100 of you swear by your gage, who says your right, thoughts?
Agreed. Accuracy is a crap shoot with most gauges, but I have found the quality names are pretty consistent. I have a good OTC one that is consistent with the expected cranking pressure for the last small block I put together.
But you are very right that the diagnostic value of a compression test is to detect differences between cylinders.
 

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Gauge difference also temp will make a difference. Same gauge on same cylinder checking compression at 50* vs 120* will show different results. A pickled motor, prior to burning the extra oil out will be different then one that had it burnt off.
 

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I always use the same compression tester and thats why i always test my new sleds from brand new so i know what it was from the start. Last sled i had 8000km and the compression was the same as it was new with the same compression tester.

just be concerned if the difference between cyl is getting worse
 

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pretty easy to test or check your compression tester. we have a fitting for this. hook to a air line and compare the air pressure gauge with the compression tester gauge. by following the above, that would mean tire air pressure testers aren't accurate? that could be fatal. and yes the cheap ones are always off. SNAP-ON, OTC, ETC. were all right on.
 

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2021 Matryx 850 Vr1 137
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I always use the same compression tester and thats why i always test my new sleds from brand new so i know what it was from the start. Last sled i had 8000km and the compression was the same as it was new with the same compression tester.

just be concerned if the difference between cyl is getting worse
Idk about u but the last 4 Polaris sleds I've bought always tested low when brand new. Around 5-800mi is where they started testing where they should be. Idk if its cause the rings and synthetic oil 🤷‍♂️ but new they never tested over 120
 

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2020 Indy XCR 800 129", 2019 Indy 850 129", 2011 IQ Turbo 121"
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It isn't a Matryx, but is an 850. Mine shows about 125psi on a warm engine, pulling it over one-handed. I've got just short of 9500 miles on it. Still have coating on the piston skirts, though it is worn off near the tops of the pistons.
 
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