What causes this? Is it ok? If its hot and I shut it off it sounds like a gunshot sometimes. I know its only unburned fuel but man it's loud. Any one elses doing it? I have an 2000 Quadmaster 500

 

It's probably jetted wrong, what color is the ceramic tip of the spark plug?

 

bike calls for NGK CR6E plug. Plug in bike was CR8E. When I took it out it was black. I put the CR6E in it. It runs fine but sometimes the idle skips and it stalls. I am going to spray the carb. I don't want to take it completely out but i'll take the side plastic cover off I guess? Is that where the jets are?

 

if it's not idling steady you probably need to richen up the idle mixture. there should be a single brass screw under the carb, try turning it out slowly as it's running and see if the idle gets better.

 

Is the screw under the bowl?

 

Look in front of the bowl, on the underside of the carb.

Are you using pure gas? or ethenol blended stuff? If youre using blended gas, try a tankful of pure gas first, that may be all thats needed.

Hows the exhaust system? holes or leaks?

 

no leaks, she quite

 

I am having same problem with same machine

 

Well, don't start messing with the idle mix screw. Can be an air leak into exhaust or mixture out because of dirt in the carb, stuck choke, dirty air filter etc. I would clean the jets and check the exhaust joints are not leaking air. Backfires can blow the baffles out of the exhaust. Honda 450s are prone to backfires and it is the only model where I have had to fit new silencers in order to quieten them again.