Who's running Regular
Road Master
Joined: May 2009
Posts: 1,231
Likes: 5
From: In the north
I don't sweat it and burn what ever comes out of the hose. I have filled up with premium a couple times. Bike was actually less responsive and harder on gas. But then if you want to pay for extra additives then that is your choice. Them additives just slow down the burn and reduce its tendency to fire under compression under severe loads.
Road Warrior
Joined: Jun 2009
Posts: 1,342
Likes: 0
From: Western Wisconsin
Where I buy my gas in town, 87 regular is 10% corn.....the 89 mid and 92 high are 100% gas.
For the extra 10 or 20 cents a gallon I get all gas, plus I use a 4 cent off per gallon coupon for shopping there.
All the other stations in town are 10% corn in all three.
For the extra 10 or 20 cents a gallon I get all gas, plus I use a 4 cent off per gallon coupon for shopping there.
All the other stations in town are 10% corn in all three.
Elite HDF Member
Joined: May 2006
Posts: 3,927
Likes: 5
From: Midwest
You've gotta love it. The guys who burn premium "just because it's only a nickel more and I don't have a clue whether regular would work" have every right to do so. But that's pretty weak logic to try to convert the unsaved.
It reminds me of an old man-on-the-street comedy bit:
Q: "Sir, which do you think is worse...ignorance or apathy?"
A: "I don't know, and I don't care".
It reminds me of an old man-on-the-street comedy bit:
Q: "Sir, which do you think is worse...ignorance or apathy?"
A: "I don't know, and I don't care".
Outstanding HDF Member
Joined: Jan 2011
Posts: 2,590
Likes: 31
From: Western Illinois, land of bad roads, and corrupt politicians
OK so I have a 120 CI, Straight pipes, 3 racing tuners, A blower....... and am wondering....
Why do I only get 28 mpg ?
Why do I only get 28 mpg ?
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Extreme HDF Member
Joined: Sep 2005
Posts: 11,615
Likes: 50
From: Baton Rouge, LA
You can run any fuel grade you want as long as you avoid detonation. The problem is that with modern bikes you can have incipient detonation that you don't hear, and the ECM will compensate by retarding the ignition advance until the event stops, up to a set maximum (-8° is stock for my '07). When this happens you will lose some performance and the engine will likely run a bit hotter.
Premium gas in itself will not make the engine run cooler, but any gas will increase engine temperatures if detonation occurs, even if kept in check by the ECM's knock retard function. Some years back Consumer Reports magazine tested various grades of gas in cars designed for regular and found that neither temperature nor performance was affected by the grade chosen. My turbo car requires 91 octane, and if I use regular it runs poorly because the ECM backs-off on the turbo boost as it senses detonation. The bike and AFAIK most other non-turbo vehicles do the same except with ignition advance.
If the bike is tuned for premium I would just bite the bullet and run the right grade. With stock compression you could probably tune the bike to run regular, but there would be a performance and probably a minor temperature hit. IMO it isn't worth it.
Premium gas in itself will not make the engine run cooler, but any gas will increase engine temperatures if detonation occurs, even if kept in check by the ECM's knock retard function. Some years back Consumer Reports magazine tested various grades of gas in cars designed for regular and found that neither temperature nor performance was affected by the grade chosen. My turbo car requires 91 octane, and if I use regular it runs poorly because the ECM backs-off on the turbo boost as it senses detonation. The bike and AFAIK most other non-turbo vehicles do the same except with ignition advance.
If the bike is tuned for premium I would just bite the bullet and run the right grade. With stock compression you could probably tune the bike to run regular, but there would be a performance and probably a minor temperature hit. IMO it isn't worth it.
Road Warrior
Joined: Dec 2008
Posts: 1,616
Likes: 17
From: Mid West
On two road trips I confirmed the mileage per gallon difference from 87 to 93 at 5mpg for my bike; same basic road conditions only could not find 93 or 91 so had to fill on 87 and lost the economy. Tried several times in home town on back and forth to work, bike got less than 35mpg on 87, back up to 41 on 93 and variable 38-40 on 91, same miles same speeds.
As to cooler, my oil temp runs 5-10 degrees cooler when I run the higher octane as I suspect the engine works some less to make the same HP on the higher grade gas. Again back and forth to work, same miles same speeds, roughly same temps during summer; also the bike pings in the higher heat times of the year on the lower grade gas(less than 91) and I am almost deaf but still hear it.
As to cooler, my oil temp runs 5-10 degrees cooler when I run the higher octane as I suspect the engine works some less to make the same HP on the higher grade gas. Again back and forth to work, same miles same speeds, roughly same temps during summer; also the bike pings in the higher heat times of the year on the lower grade gas(less than 91) and I am almost deaf but still hear it.