Hello,

I have a 2000 Yamaha Big Bear 400. It had been sitting up for about 5 months. I replaced the battery and cranked it. Since it had been sitting idle for so long it took a while for it to crank. Once it cranked I had to have the choke open for the bike to run. After approximately 6-10 minutes, I noticed smoke coming off the exhuast pipe. The pipe was also glowing red. I turned the bike off and let it cool. I recranked it and the pipe turned red almost immediately. Does anyone have any ideas? And can anyone tell me how to fix it. Thanks for ANY help!!

 

The carb can be varnished real bad from sitting so long and not allowing enough fuel through, which would cause it to run lean and hot.

 

what color was the smoke?

 

I bet you have a jet plugged with varnish and it's running lean....

Dont let it run lean or get that hot..... if your lucky you may be able to clean out the carb with some cleaner like Seafoam. Drain the old gas, put in some new fuel and Put some thing like this in the tank and let it set for a while, start it up and see if it works it's way throught the carb. dont let it run and get hot or run lean...
if this quick fix dosnt work then pull the carb and clean it out.