compression

Hello. i ran into a weird situation yesterday and i was wandering if anyone else has seen the same thing or has any suggestions. I was just doing some rutine maintenance and had the spark plug out. I put it back in and was going to start it when i notice that it was kicking over fairly freely without the decompression lever pulled (it was not stuck either-it looked normal from the outside). i was even able to kick it over with using my hands (definately a problem). i kicked it over about 20 -30 times, and the compression started to come back to what seems to be normal, then she fired up and ran normal? what the heck is going on? The only thing i can think of is that maybe some dirt got in thrue the spark plug hole and held a valve open or something. Matt.

Matt,

Your problem has been seen before by at least 2 other TT'ers. It may be directly linked to your compression release.

Both other guys compression came back as well.

i've had it as well and so have so many others. don't panic!

basically if they decide not to start and you kick them over long enough they seem to lose compression. my answer was to leave it alone for about 3 days as well as fresh fuel and plug burnt off on the gas cooker.

the bike started up and when i stopped it and did the compression kick it was solid again. it can't be anything but the rings and i feel it must be something to do with fuel wash on one face of the bore allowing the rings to sit off the cylinder wall on that side allowing the fuel charge by.

Taffy

I agree with Taffy, most people have said they needed to pull the hot start to get it running, that is a definate sign of flooding, I think that it doesn't take alot of fuel to wash the oil off the cylinder wall.(Short stroke makes this a big issue). My WR would do that from time to time. After I got it running the compression would return. Don't worry about it.

Dave

Matt, If there is no compression at the kick starter then there is a mechanical problem.

pull the valve cover and see if the valve bucket is staying down(or if it has way more clearance than normal)on the compression release side. The bucket will mushroom over slightly and cause it to "STICK" in the shim bucket bore. sometimes turning the motor over frees it temporarily BUT!!! you must remove the bucket and chamfer the top edge! because the problem will reappear and could bend that valve or worse if it hangs down deep enough, besides the damage it is doing to the bucket bore. PT

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