I have a Coolster 125 ATV (3125R), When it idles I can hear an occasional misfire. Doesn't sound very happy if you ask me. I've changed the plug and it made no difference. I didn't see any carb adjustments other than the idle rpm.

Got any suggestions on things I can check?

Thanks!

 

After further research I think I'm going to change the fuel filter as well as clean the carb. I think the dirt may have come from the horrible stock air filter it has on it. I'm thinking of replacing that too. Does anyone know if it's ok to remove the hose that runs from the very top of the air filter to the case? (I'm assuming this hose was to meet some EPA requirements or something.) Lastly I'm planning on removing the hose alltogether and plug the end that goes to the case somehow.

Comments and suggestions are welcome.
Thanks!