I use the cheap gas(regular unleaded) and I haven't had any problems whatsoever. I don't know if premium unleaded would hurt anything. I do know a buddy of mine was using this stuff called "octane boost" and he burned his valves so bad they needed to be replaced. So with that in mind it's your call. The cheap fuel works just fine and the way I see it is why pay more money for premium when regular works great.
A forum community dedicated to Yamaha Grizzly owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more! Open to all Grizzly models including 700, 660, 600, 350, and 125.