What Octane fuel do you run?

Remember, octane can effect speed of the flame front as well as knock resistance. This why you are not actually harming a motor if you use too high an octane, but can certainly Damage one with too low an octane.

There is a lot more than just octane that determines burn speed, sedatives, specific gravity etc. What he said about excess fuel in the cat and on the o2 sensor are valid points, but there's much more than just octane as the predictor.

The best bet is run the gas your ignition timing was set to, be it stock or modified, stick with what it was tuned for. Running 87/89/91/93 will be a very slight change in power if your bike isn't tuned to it, and your not doing the motor any favors running premium through it, quite literally burning money needlessly running 91+ on a stock timing bike.

Anecdotally, there is a large number of people who had a worse running bike using premium vs mid grade, which was resolved going back to mid grade in the Daytona 955i community. Probably a result of "right on the money" ignition timing when paired with 89 on those motors.

Its a bit like oil though, people will run what their grey matter tells them they feel like running, and honestly its not a huge deal.
 
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I generally ran 89 or 91 in mine but also 87 on occasion and didn't notice any difference. While riding across country several times there were areas in the west where regular was 85 and premium 89. I was told it had something to with the altitude.

My Rocket Classic Tourer had Jardines or TORs and a custom tune with secondaries open and the speed limiter disabled.
 
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The original Rocket manual says to use 89. However, later on the Workshop Manual says to use 87. I phoned Triumph USA a few years back and asked them which is correct. They said that it will run fine on 87 and that is all that is needed. However, later on he added that if it pings then go to 89. I don't know of anyone who has had a pinging problem, but that is nothing that can't be easily fixed anyway. I have just shy of 130,000 miles on 87.
I'm looking at my owner's manual and it clearly specifies (@p. 99) 87. I've run 87 since new without a problem. However, I've just found a station which offers 87 non-ethanol and I've noticed about a 2+ MPG increase. Not enough experience yet to generalize. But the stuff is $0.50/gal. more expensive - so I'm not sure it's worth the increase. I'll keep you advised.
 
It is worth it. I to run what the manual specifies 87 octane. We have two gas stations here in henryetta Oklahoma and both just sell regular gas. No ethanol offered. I have had to get gas where all they offered was the ethanol and can tell the difference.
 
I use 91 which is Premium in Canada. 87 (regular) has ethanol in it. My bike runs fine on 87 and I won't drive around all day looking for Premium, but when it's there I use it just to avoid ethanol.
 
Incorrect. Octane rating is simply a measure of the fuel's ability to resist detonation (not to be confused with pre-ignition). It has nothing to do with how complete the fuel/air mixture is burned or how much is wasted. Running a fuel octane higher than what the engineers recommended will NOT harm the engine in any way but it is a waste of money if the engine is not setup to take advantage of the fuel such as running high compression or advanced timing.

You always want to run the lowest possible fuel octane in the engine that it can safely withstand without signs of detonation. Otherwise, it is perfectly safe to run high octane fuel in these bikes if you want. I generally run 92 octane fuel simply because of the summer heat and I hammer on my bike a lot with periods of high loading at lower rpms where detonation is more likely to occur. Honda engineers did a really good study of fuel octane and engine rpm years ago which showed that detonation is only a concern at lower rpms levels and high engine loading.

We will have to agree to disagree on your first paragraph. Octane does indeed have an impact on the propagation of the flame front in addition to the resistance to explosive detonation. We can agree that running higher octane is a wasteful practice.
 
Its not an opinion, octane itself does nothing to speed or slow the flame front.

If you read the links I put up they will explain it. Speed of flame propogation is based on specific gravity, or the density, of the fuel and its composition.

There are fuels with a very high octane, over 110, that have a slower flame propagation by a huge amount compared to 87 octane pump gas.

Ethanol based fuels are a good example of octane vs flame speed when compared to gasoline.
 
I use 91 which is Premium in Canada. 87 (regular) has ethanol in it. My bike runs fine on 87 and I won't drive around all day looking for Premium, but when it's there I use it just to avoid ethanol.

Are you saying the 91 has NO ethanol?
 
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