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Just curious what octane gas everyone is running? I should probably check the owners manual :D wasn't sure if they might run better on lower octane or higher, we have the options of 87,89, and 93 here
 

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we got 95 and 98 here. i use 95 cuz it's cheaper

recently went to austria where they have 98 and 100 octane. i was quite surprised.

btw there is already a thread like this
 

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manual says to use of 86... so i'll use either 87 or 89... depends on how rich i feel
 

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We get~
91 ($1.45),
95 ($1.50) premium,
98 ($1.55) Ultimate

The 91 has deteriorated in quality and longevity since the 10% Ethanol went in and being a boatie I wont go near the stuff.

Proven it time and time again in all my vehicles 15-20% better economy & more responsiveness on 95 and its only a few cents extra.
 

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Different for different countries...... so check your manual

In the USA octane is measured differently. USA 87 is about the same as 91 elsewhere.

In Thailand 91 is benzine / gasoline, and it is mainly used in motorcycles.

The 91 and 95 gasohol (blended with ethanol) that they also sell in Thailand is ok for all motorcycles made in the past 5 or 6 years, but not for many of the older ones. Most cars made since the mid '90s are gasohol compatible.

Ethanol has a lower calorific value than gasoline, so you will go further on a tank of pure gasoline than you will on a blend.

Ethanol is quite corrosive..... and the greenness / ethics of biofuels is questionable. I am not convinced. If you wanna go green, ride a bicycle. I do, a lot.
 

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I hear the Noth Americans on here speak of 'storage' during winter.. must be **** cold lol.. If you do this dont use ethanol, like a boat fuel tank condensation builds up.
 

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I used 93 .
For U.S. owners, 87 octane is fine. 87 without Ethanol is the best of everything - power, mileage, cost. I saw a 4% increase in MPG from using Ethanol-free gas.

The only reason to go up from 87 is to stop detonation. Lower elevations and colder temps may cause detonation, but for most, 87 octane is optimum. If you don't have detonation, excess octane will lower performance and mileage.

You aren't doing your engine any favors by running a higher octane fuel than needed - just lowering performance and increasing your cost.
 

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I accidentally put 91 (US which is 87, 89, and 91) in my bike yesterday. I went to an unfamiliar gas station and they had the regular and premium fuel flip flopped from what I'm used to. I already started the pump when I noticed so I went with it.

The performance gains of premium over the regular (87) that I have been using since day one are exactly as I suspected they would be. Zilch. Zero. Nil.
It was a waste of money in my opinion for an engine that runs 10.7:1 compression.
 

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Well my book says 87 or higher so I run premo. I run either premium or race fuel in everything I own except my truck. But everything I have is set up for it. And once I Get my bike back from Fuel Moto USA for R&D it will have a shaved head with port work so it will never see anything less than 93.
 

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Well my book says 87 or higher so I run premo. I run either premium or race fuel in everything I own except my truck. But everything I have is set up for it. And once I Get my bike back from Fuel Moto USA for R&D it will have a shaved head with port work so it will never see anything less than 93.
OK, for a modded (higher compression) engine it may be required.

Keep in mind if you are looking for the best performance from an engine (like you must be) just running the highest octane gas available is costing you power. You want the lowest octane level that just barely holds-off detonation.

Many moderately tuned race engines will produce more power on pump gas than a high octane race gas, but because the "spec gas" is required they all have to use it.

You need to run the modded engine on a dyno with different fuels to know what is best. Higher isn't better. Proper octane fuel is a simple way to get all of the potential power from a modified engine.
 
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