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Since i bought the bike i have been using 93 and i am getting 47.9 mpg, no popping sound in deceleration. I know the manual says that i can use 87, but not sure if i should? What you guys using ?


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I was pleasantly surprised to see this recommendation when reading the owners manual.

The ECU very accurately meters fuel while monitoring all engine parameters. "Knock" or detonation is one of the things it's looking at and effectively prevents. Because of this, there's no reason not to use the mid-grade fuel. Going to a higher octane will not yield more power, so go ahead and save the few pennies when gassing up.
 

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Higher octane is not necessarily "better". It is more resistant to detonation, which can be good if you have a very high compression engine or one that has a lot of carbon deposits and "pings" from pre-detonation. There is no additional energy in premium. Your mileage should not be adversely affected by using 87. If it runs well on 87, using 93 is just giving away additional money to the oil companies.
Save your money.
 

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Here in Missouri we have Rec 91...this is ethanol free gas used in motorhomes. I have been using this in my Thunderbird with no problems. It does cost a few pennies more than premium.
 

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I have used 87/89/93 in my T120 and cannot tell any difference in the way the engine performs. I have not checked the mpg yet but have been meaning to and will post later. There are a couple of stations in my area that sell non-ethanol 87/93 and I use the 87 when it is convenient for me.
 

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Since i bought the bike i have been using 93 and i am getting 47.9 mpg, no popping sound in deceleration. I know the manual says that i can use 87, but not sure if i should? What you guys using ?

I'll check my actual manual when I get home but from the online one : http://images.triumphmotorcycles.co...et twin/25 09 2015/ohb_dp-de-de2-du_en_01.pdf

They seems to want you to use 91, maybe I'm missing something?

"Your Triumph engine is designed to use unleaded fuel and will give optimum performance if the correct grade of fuel is used. Always use unleaded fuel with a minimum octane rating of 91 RON."
 

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The RON rating does not equal the typical US octane rating:

USA (AKI/PON) --- Europe (RON)

87 = 91
89 = 93
91 = 95
93 = 98

So when the manual says 91 RON, that's 87 in the U.S. With a 10 x 1 compression ratio, you don't need higher octane. If you are at an iffy location, and want to make sure you don't get something too low, you can always fork over the cash for higher octane. Typically, in the USA, you don't have to worry. If you are putting premium gas in your tank, you are essentially burning money.
 

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Standards are hard.. Thank you!

The RON rating does not equal the typical US octane rating:

USA (AKI/PON) --- Europe (RON)

87 = 91
89 = 93
91 = 95
93 = 98

So when the manual says 91 RON, that's 87 in the U.S. With a 10 x 1 compression ratio, you don't need higher octane. If you are at an iffy location, and want to make sure you don't get something too low, you can always fork over the cash for higher octane. Typically, in the USA, you don't have to worry. If you are putting premium gas in your tank, you are essentially burning money.
 

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You can use the highest octane gas, but it won't do anything. There are plenty of threads on this site alone, so I won't repeat the points again. I use regular 87 on both Scrambler and STR and they both run strong and smooth.
 

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In other words; "I love giving money to the oil companies for absolutely nothing in return."
The better grades of brand name fuels contain better (more than US EPA-required) additive packages. From experience, they reduce carbon deposits and keep throttle bodies, etc. cleaner. Hardly a major expense although I'd agree in a Bonneville you won't see much if any mileage improvement. Generally I use BP/Amoco or occasionally E-0 when I spot some on the road.

On the other hand, the three European car engines in my toy box all specify 93 M+R/2 fuel, so a no-brainer. Could never train some of my highline car clients to buy premium over 87 or mid-grade. Then they complained about their mileage. :D Three tanks of the good stuff and they saw a ~ 15% improvement. Pays for the difference at the pump while getting the better additive package.

Since our bikes lack knock sensors which can advance the timing with higher octane, little real or measurable performance or mileage boost. Pity...
 

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Since our bikes lack knock sensors which can advance the timing with higher octane, little real or measurable performance or mileage boost. Pity...
Do we know that for sure on the latest version of this engine? It would be extremely interesting to know if ignition timing maps do adjust for fuel quality based on knock sensors or other parameters.
 

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93 real gas (no ethanol) 60mpg. 91 Unleaded (ethanol) Gas 41mpg. Same trip, roads, riding and revs. So I don't measure the "You don't get what you pay for" .
2009 T-100 all pollution gear off of pipes and airbox. End baffles removed and drilled through. Crankcase breather rerouted. Temp Sensor located outside of the airbox. High volume air filter installed. Modified map created from a Thruxton Air Fuel Table to avoid running lean.
 

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93 real gas (no ethanol) 60mpg. 91 Unleaded (ethanol) Gas 41mpg. Same trip, roads, riding and revs. So I don't measure the "You don't get what you pay for" .
That's impressive since E-0 normally averages ~ 10% more mileage vs E-10 in all my toys.
 

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93 real gas (no ethanol) 60mpg. 91 Unleaded (ethanol) Gas 41mpg. Same trip, roads, riding and revs. So I don't measure the "You don't get what you pay for" .
The real difference in your example is the no-ethanol vs ethanol fuel. Ethanol has something like 1/3 less energy than real gas. So you have to burn more of it per mile.

I would bet the octane rating (93 vs 91) makes almost no difference in your comparison.

I think you "got what you paid for" because you paid more for the real gas (aka the good stuff).

-Alan
 

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You don't go from 40 mpg to 60 mpg because of gas type/octane. This is exactly why science isn't conducted via misc anecdotes.

But as they say, if it feels good then do it :)

I do wonder though what the miles per dollar between the 87 and the 93 is though ... but I'm not so much that I'm going to do research and math.
 

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You don't go from 40 mpg to 60 mpg because of gas type/octane. This is exactly why science isn't conducted via misc anecdotes.

But as they say, if it feels good then do it :)

I do wonder though what the miles per dollar between the 87 and the 93 is though ... but I'm not so much that I'm going to do research and math.
Loads of E-0 91 M+R/2 in Madison though..., so THAT'S an easy test for you to try. Figure easily 10% more MPG. http://www.pure-gas.org/index.jsp?stateprov=WI
 

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Thanks man, but living here I am pretty aware of the gas that's at the gas stations, first hand knowledge and all. Sometimes I run 87 E10, sometimes I run 91 E0. My gas mileage is always somewhere around 45mpg. Just one more anecdote I know, but it doesn't make a noticeable difference on my bike.

Our gas mileage is very dependent on our right hand, and even tailwinds. I think those have a far bigger effect than gas type.

YMMV
 
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