I have a new grizzly09 and I have not put any gas in it yet. What octane is the best to use on braking in a new machine? The state that I live in has 87, 89 and 93 octane. I have a grizzly05 that was used when I bought it and I have been running 93 octane. Any suggestions.

Thank you,
morrisatv

 

This issue was addressed on Grizzly Central not all that long ago and I would go with the higher octane.

Of course this was after I broke both my Rhino and Grizzly in with 87 octane, no problems, but the manual recommends a higher octane or at least my 08 did, you might want to check your manual just to make sure.

 

Fuel octane has nothing to do with break-in. The only thing that should effect your octane selection is compression. With higher octane fuel you are losing power and throwing away money. Most stock ATV engines only need 87 octane including the grizzly. If you were to get a high compression piston then you could run higher octane fuel.

All the octane of the fuel changes is the resistance the fuel has to combustion. Running a high octane fuel in a low octane required engine will just detonate the fuel later than it needs which is why it loses power.

Running octane too low for your engine will result in pre-detonation which does all sorts of bad things.

Best thing you can do for break in is make sure the engine is completely warm and run a high quality wet clutch compatible synthetic oil.

Hope this helps,
Kevin

 

i doubt your bike has high compression so it would suprise me if you would have to run anything higher than 87, my bike has higher compression so i usually run 90+ octane, but you never know maybe yamaha has some wierd reason why they want you to break it in with a higher octane lol.

 

JLSparky7 and 91Warrior357 are correct. When all else fails, check or recheck your manual. I am now going back to straight pump gas as mine ran no differently on 87 than 91. Sorry for the bad information.

The manual on my Rhino and Grizzly states, "Your Yamaha engine has been designed to use regular unleaded gasoline with a pump octane number [(R+M)/2]of 86 or higher or a research octane number of 91 or higher. If knocking or pinging occurs, use a different brand of gasoline or 'premium' unleaded fuel."