i have a 150cc pit bike, i was riding it the other day and went down in gears a little to quick and everything just shutdown.... when i went to kick it the kick start just went straight down with ease... i then put it in gear to check for compression and nothing just rolled as if it wern't in gear at all... i have no idea whats happened???
Compression and Gear Problems
- Thread starter J3Ly
- Start date
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my67xr
Miniriders Legend and Master Spanner Spinning Mode
hi, welcome to miniriders.
if you pull the spark plug out first
it might pay to take the 2 small rocker covers off of the head, the one at the top, and one on the underside.
just check out the the valves are opening and closing as you kick it over by hand.
if the rockers don't move up and down when you are kicking it over, then the problem is most likely somewhere else.
it may have broken a kickstart gear ?
have you ever adjusted the valves on your engine ?
they are set too tight when they are assembled at the factory.
here is a video explaining how to check/adjust the clearances.
the video is of a smaller horizontal engine, but will give you a good idea on how to do it.
most of us run them slightly tighter, we set them at .003" intake, and .004" exhaust
http://www.youtube.com/watch?v=QJciyJRJh8Q
if you pull the spark plug out first
it might pay to take the 2 small rocker covers off of the head, the one at the top, and one on the underside.
just check out the the valves are opening and closing as you kick it over by hand.
if the rockers don't move up and down when you are kicking it over, then the problem is most likely somewhere else.
it may have broken a kickstart gear ?
have you ever adjusted the valves on your engine ?
they are set too tight when they are assembled at the factory.
here is a video explaining how to check/adjust the clearances.
the video is of a smaller horizontal engine, but will give you a good idea on how to do it.
most of us run them slightly tighter, we set them at .003" intake, and .004" exhaust
http://www.youtube.com/watch?v=QJciyJRJh8Q
Last edited:
do what my67r is saying..
if that does not work out then yes you most likley have a bent valve to say the least... lets hope its only a little bent and did not ruin too much...
if it is bent and or valve is not closing when your adjusting the valves prepare your wallet its most likely going to be bad if the head is damaged you may aswell buy another motor.. if the head is usable then you will need new valves new bore and piston
