Lets talk about gasoline and its octane.

[DavidofColorado]

My bike says to use 91 octane and if I don't the engine will self destruct or something to that effect. I am not worried about the price difference as much as I am that the gas I am buying isn't all that different from one button to the next. I filled up with mid grade the other day and I haven't heard knocking or anything bad. I am just wondering what your thoughts are on it. Do you just buy the premium and call it a day or what?

[dchd1130]

Dude do a search octane threads are like oil threads. You will get all kinds of differnt answers. What octane fuel you to use will vary by what alltitude you are at. Your owners manual was writen assuming you are at sea level. Your not. The barimetric presure is lower at our alltitude so you can run a lower octane fuel here then you could at sea level. Baisicly your compression is lower here. Higher compression engines require higher octane fuel to avoid pre ignition of the fuel (knocking).

[Gramps]

:imwithstupid:

[swademaster]

You could probably run 85 with no problems.

[DavidofColorado]

Thanks I never heard it put that way before. I appriciate you thoughts on it. So I should be able to run even better the higher up in the hills I go? Cool.

[Canuck]

85 is better for your bike than the higher grades, (race fuels aside).

[DavidofColorado]

I filled up with race fuel once and I had a hard time keeping it idling. Is there any low octane race fuel out there that you can recommend?

[Canuck]

Nope. Need to have your ecu remapped for race fuel.

[DavidofColorado]

I have a carbed bike. Would that require re jetting it?

[JOE!!!!!!]

Yes, your carbs would have to be re-jetted for any race fuel. But it's a total waste of money to run race fuel on the street. For that matter, if the jetting you have is original, you should re-jet (retune, really) for Denver's altitude. And just run regular or mid-grade. Maybe premium if it's like over 100 in the summer. Also, your motor will run worse the higher up in altitude you go, but if you have it tuned for 5000 feet, you'll have a good compromise for running around town and in the canyons. The altitude thing is a tuning issue, not a gasoline issue.

[krod]

Where ya been hiding out JOE?