Recently my Grizz has a developed a new problem. It's not the stalling issues that's inherent with these bikes when they are new. What's happening is that while I'm plowing snow, I have it on low and have the revs up. I push the snow in to the snow pile and throttle the bike a bit for the last push. Once I come off the throttle the bike just dies. Is this just an ajdustment on my fuel controller?