You shouldn't need to put higher octane fuel than what yamaha suggests in their beasts.Might be from use of low-octane fuel...have you tried switching to 94 for a few tanks?
Used to have this problem with my car...switching to 94 solved the said problem...
Sounds crazy, but it worked...
This is a rather old post — almost two years old now. He also mentioned he was using 91 octane gas, which is generally as high as it gets in the states. I know (in Washington) our gas is 87, 89, and 92. I haven't seen 94 yet on my road-trips in the states.Might be from use of low-octane fuel...have you tried switching to 94 for a few tanks?
Used to have this problem with my car...switching to 94 solved the said problem...
Sounds crazy, but it worked...