Valve adjustmants made, now no compression!

[Rocky_mx]

Hi, just got my new shims in today, clearence now seems all good. Put it all back together and it has no compression!

This is on a yz 250f 01

I have done everything the manual said.

I had a radiator off and oil drained.

The cams all lined up and 12 pins inbetween etc..

I dont get it! Have i missed something!!!! I was getting dark!

[cowboyona426]

Are you sure the cams are timed to the crank correctly?

[Rocky_mx]

Originally Posted by cowboyona426

Are you sure the cams are timed to the crank correctly?

Well it look to be as it should, all lined up with the timing mark!

its wiered! If a valve is slightly out will it amke a difference?

Maybe i took wrong readings?

[cowboyona426]

I would double and triple check the valve clearances and the timing. Rotate the motor through a few times and check it again. Also make sure your decomp cable isn't hanging up (if you still have the manual decomp lever). And, make sure you have the spark plug in

[Rocky_mx]

Originally Posted by cowboyona426

I would double and triple check the valve clearances and the timing. Rotate the motor through a few times and check it again. Also make sure your decomp cable isn't hanging up (if you still have the manual decomp lever). And, make sure you have the spark plug in

It was the exhaust valves! Far too tight! I did the wrong settings... intact on exhaust! Anyhow sorted it and started up 1st kick! Ran perfect for 30mins then my bottom end went!!!! So crank or big ends starting to seize!

Problems after problems!

[crdude]

sorry to hear about your bad luck, have fun gettin that 4 stroke runnin again.