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400thacker
02-04-2011, 07:18 PM
i bought this quad (250X) with the top end off of it and when i put it back together i had very little compression.

i put the top end on and left the cam out so i could see how much compression it had.
I checked the top ring and it had very little gap, looked to be new rings. my next guess was the head and it looks to be in good shape.
I turned the head upside down and put gas on top of the valve and it's been setting for a few hours and hasn't lost very much liquid at all. none of the valves are sticking or appear to be bent. they look seated pretty well

when I kicked it over i could hear a little bit of air coming from somewhere but i couldn't figure out where. seemed to be on the compression stroke.
btw the head gasket is new.

it has compression but quite a bit less than my stock 250x and this one has a 12:1 weisco in it.

anyone have any ideas or things to check besides changing the head or getting another set of rings?

thanks

michirider
02-05-2011, 03:23 AM
first thing you can do is put a little bit of oil into the cylinder (i mean a small amount like a few drops) and do your compression test again. if you gain compression the rings are to blame. and also remember the gaps on the piston rings should not line up if they do that could cause the problem.

dman66
02-05-2011, 05:33 AM
Tried to send you a PM but your mail box is full.

400thacker
02-05-2011, 10:26 AM
the rings are not lines up and i had a little oil in it as i always do , when i freshen up a top end.

the only ring that I gapped was the top one, i was assuming the others were good so I think I will try and gap them all to be sure.

DMAN - I am deleting out of my inbox in just a sec