can you loose compression through jacked up v force 3 reeds

have a 06 yz125, redone cylinder by us chrome and measured by yamaha shop, new piston, ring, gaskets, and crank seals, replacement v force 3 reed pedals and gasket , all broken in, 4 gallons of gas ran through the bike did a compression test cold got 120 psi, hot got 135, poured oil into the cylinder and hit 165psi, ripped it apart again took the cylinder to the yami shop had it measured along with the piston, its good and the rings were broken in they said, im stuck , i even checked for leaks in the crank seals after i did theme, there good, i have v force 3 reeds on the bike, the bike had theme on when i bought it used, and i replaced the pedals and noticed you can see light coming through where the pedal meets the PLASTIC CAGE, also replaced the reed gasket, could that be my low compression cause? any one, i need alota help now, all ready spent way to much money and time, the bike runs great though, if i wanted to i could sell it and no one would even know there was a problem, when i bought the bike it had less than 100psi of compression and still started 2 kick, the cylinder helped a little bit but still, everyone says 135 is just to low and i agree, gotta be the reeds, but then again i poured oil in the cylinder and hit 165 psi, could that oil seal the reeds for a short time

Reeds can cause lower compression, but that's no your issue if oiling the rings raised it. How's the surface finish on the cylinder? Have you measured the head volume to determine if it's been modified to lower compression?

You did take your compression measurements with the throttle held full open, right? If not that's why you're seeing such low numbers.

With new top end I would expect around 240 psi on this bike. But you're saying it runs good, is it possible your gauge is way off?

i think this is why the manufacturers dont supply compression test numbers: they very so widely and sometimes are not accurate....

Oh sorry, I missed it's a 125, I thought it was a 250. You should see 200-220 psi on a 125.

yes, held wide open, but if the oil gets kicked a couple of times to circulate it the air pushing out of the reeds would bring the oil to theme? im stuck, yeah the cylinder was just measured out and inspected and the guy said it looked great, i can see a gap where the pedals are suposed to sit on the cage? im at 135 hot, soo not that far if if its not that any more suggestions, 200-220 is a tone, im shooting for 165 psi, the yamaha people said 150 is what you should be looking for

and how do you measure head volume? is that the same thing as the squish

did the yamaha shop check ring gap? it could have a bit too much...

they measured the piston clearance and everything, when i put the bike together the first time i measured it, dont remember the exact number of the ring gap, but remember for shur it was on the small side of the spec in the manuel

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