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Posted

I have taken the carb off and cleaned thoroughly, drained the tank, and replaced the spark plug. Will start right up, and runs fine for a sec, and thens starts cutting out like it is misfiring or something. Will stay running while i hold throttle (Still running rough), but when i let go, it quits. Will not start again, until it sits for a day, or i drain fuel and replace again. Could it have jumped time?

Posted

It is possible that it jumped time, there should be a bolt above the flywheel that you can remove to see the timing mark on the flywheel. There should be a "T" on the flywheel indicating that the motor is at TDC. Take the valve cover off, rotate the motor until the "T" appears in the hole and the vavles are closed, you should be able to tell by the position of the cam lobes. This will be TDC on the compression stroke. There should be marks on the cam sprockets, I don't know if there will be marks on the head or chain for you to reference, but there is a specific spot that they should be at when the motor is at TDC on the compression stroke. You may need to consult a dealer or just get a repair manual, you should have one anyway.

There are alot of other possibilities too, maybe you didn't clean the carb well enough, the carb must be completely dis assembled, every little screw, jet everything. Then every thing should be hand cleaned. A wire brush, a torch tip cleaner is handy, or something similar, some carb cleaner, you need to clean every nook and cranny, then blow through all the passages with compressed air. Make sure to get the pilot circuit, jets clear.

You could also be having trouble with your ignition system, most likey problem there is the CDI or coil.

I would strongly recommend getting a repair manual, it will have troubleshooting tips and tell you how to test some of the ignition components. Good luck.

Posted

OK, thanks! I will see what I can come up with, as I do have a repair manual, and was just hoping that wasn't what it was (timing). Is it possible that it is just an air mixture issue in my carb? I mean it cranks and runs find until it gets to running temp, and then is starts sputtering......

Posted

That leads me to think ignition, that is if it rides and performs ok until it gets warm, not just idles ok. A decent repair manual will have some direct resistance tests you can do to test some of the ignition parts, but I would be most suspect of the CDI. At any rate, use the manuals troubleshooting guide, hopefully you can norrow down the possibilities and find the problem, good luck.

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