OK, so I took the beast out today to play in the snow... first time riding since I got it. It ran fine for about 15 mins or so, then had a hard time staying running. When starting it, it would backfire sometimes and also it would rebound the kicker once in a while.. The only way i could get it started again was to pull the choke out halfway and give it lots of gas. Any clues to as what this can be?