1990 Kawasaki Bayou 300 Intake and Exhaust Pop

[marlon smith]

1990 kawasaki bayou 300c idles fine but pops out exhaust and intake when trying to excel, will not take throttle past 1/4 , any one had this problem?

have replaced carb twice, same thing, fresh built engine cylinder head, same as before, new spark plug, flywheel key is good, pulser test good, good spark

Edited February 24, 2024 by Admin
Long topic title, moved to Kawasaki ATV forum

[Gwbarm]

I would check the timing to make sure nothing moved while replacing the cylinder.

[Mech]

So it had this same problem before you replaced the carb twice, and did the head up ?

Initial impression, since it's popping out the inlet and exhaust, would be that your ignition is failing.. It might be that the ignition timing is going erratic.. I think I'd put a timing light on it and watch the timing and that the spark doesn't fail as I rev it up. Could be the cdi or a wiring fault.

You could also check the charging system is regulating as it should.

 

[flyinbrian365]

How were the valves, guides and seats when doing the top end? Did you adjust the valve lash to spec?

[Ajmboy]

Any change if you move the choke lever?

[MOJoe]

I know this has been a while, but if anyone else need this info. I had a similar problem with one of our 86 KLF 300A. I could not get it to start. It would fire then sputter or backfire. I took carb apart and cleaned and adjusted valves and put in fresh gas and spark plug. I was able to get it running but it was not running good and would backfire. After running I saw smoke coming from behind battery. What I found was a chafed ground wire grounding out on frame. Tracing the wire it went into left engine cover. I assume the pickup coil was not grounding properly. Fixed wire and now it runs great. 

[Gwbarm]

Thanks for the info. Great you found that lucky it didnt take out the pick up coil and CDI. It must have been only touching momentarily every so often.