So I have a 1999 Yamaha Warrior 350 and after I bought it for $1600, I rebuilt the carb on it and cleaned it out. I just ordered a pet cock to put on it but it isn't here yet. It starts just fine most of the time. It idles great. But when I put it in gear and I am riding, I can feel it lose power for a second or two then the power kicks back in, and it also backfires. Every day or so I have to clean the sparks plug with a wire brush because carbon gets built up on it. I just found out that the exhaust pipe has two holes in it about an inch wide. I don't know if the carb needs to be adjusted, or the exhaust pipe is the problem. Please let me know.