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low compression reading - I have my doubts


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I borrowed a neighbor's compression gauge and my cylinders checked in at a whopping 65 and 67 PSI according to this tool BUT i have bone stock internals, bolt-ons only, and it will easily wheelie in 3rd with no clutch and cranks easily, sometimes even 1st kick when cold.    I read on here that stock compression is ~ 125 PSI and when you get below 110, it is time to rebuild the top end.  My motor seems like it is far from needing to be rebuilt.  The gauge has to be busted, right?  ...or could there be another explanation?  Tried to do a  leak down test with the homemade tester the previous owner gave me with the bike but the tester itself broke (hard to explain this contraption LOL).   I'm just trying to re-assure myself that i shouldn't worry about it....

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it will easily wheelie in 3rd with no clutch and cranks easily, sometimes even 1st kick when cold.  

 

 

I'm just trying to re-assure myself that i shouldn't worry about it....

 

If it starts easy and runs strong, that should be enough assurance that there is nothing to worry about.

 

I'm new to all of this but from reading other threads 65 and 67 psi means it would be hard to start and would have power loss, neither of which you seem to have issues with so I would guess the tool to be inaccurate or the test procedure flawed in some way.

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Thanks guys, I feel better already!  It only took 3-4 kicks to reach the max reading each time.  I feel like I did it right, I rode it to warm up the engine then removed the spark plug wires from both cylinders and the plug from one, screwed the tester in and kicked away then swapped the tester and plug to the opposite cylinders and repeated the process.  Now if only i could figure out my shifting issues (yet another new thread of mine)

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This. Car truck mower quad. All 60 psi

Haha  ...I have been brewing beer for a few years and, the more experienced & consistent I get with each batch, the more suspect I become of the equipment we use to measure the gravity (sugar content) and temps.  Constantly calibrating the thermometers and not sure if I trust the one I am using to calibrate it with.  Same thing with the hydrometer and refractometer and the one I have is supposed to be the best

 

Damn shitty equipment!

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ill say it this way......if you truly are running 65 and 67psi you would not be able to start it.  You DEFINATELY would not be able to kick start it......it MIGHT start if you dragged it for about a mile behind a truck around 40mph haha. 

 

but in all honesty.  harbor freight compression tester is JUNK.....do your neighbor a favor and throw it away FOR HIM.....

 

and you also need to hold the throttle wide open and kick and kick and kick until the gauge stops climbing.....but you have to have a decent gauge to begin with....

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