Racing Fuel

[Motomonster]

Very wise ones,

 

The underwater anarchist and I are thinking about getting a 5-gal drum of racing fuel and adding a bit to our normal fuel to see if we dig it.

 

Is this worth it? A good or bad idea? If yes, how much should we add?

[Murray]

Depends what you mean by racing fuel if you mean the usual stuff sold which is the equivlent of AVGAS its probally marginal you really need rasied compression ratios and a few other mods to take advantage of it. Which bike acording to your signiture its a Stone or one of the cruiser models i would suggest the motor is too softly tuned to take much advantage at all you will probally notice a small difference. If you can't tell the difference between priemuim and standard pump fuel its highly unlikely you'll get much benifit form the race fuel. However some race fuels and most definatly AVGAS is still a full leaded fuel if you bike is fitted with oxygen sensors or similar it will eat it. Try about a 30-40% mix to begin with if however you are talking about stuff like ELf racing fuel I havn't had any experince with it so can't really tell you anything.

[Guest Ragin' Pit Bull]

I've used Sunoco MO2X in my Le Mans and can feel the difference! It's about 115 octane. I run it pure and I've run it mixed. The horsepower increase is noticeable.

[Motomonster]

I've used Sunoco MO2X in my Le Mans and can feel the difference! It's about 115 octane. I run it pure and I've run it mixed. The horsepower increase is noticeable.

Wow, that high? I was thinking of a bit to boost the regualr octane a bit. I've got some mods, but I don't think I have enough to do justice to 115 octane.

 

Thanks for the info.

[Guest IanJ]

So, not to rain on anyone's parade, but what octane does, in gasoline, is reduce its preignition ability. There is no advantage to running a higher-octane fuel than that which reduces knock to nothing. So, if your engine isn't knocking, you're running the most octane you'll ever need, and running higher-octane gas will cost you more money without any return in terms of power or gas mileage.

 

There's more information on fuel octane here:

 

Octane FAQ answers

 

But even if you don't read the FAQ, be aware that increasing octane over the factory recommendations is pretty much like throwing away your money, if that's the only difference between the fuels.

[Motomonster]

Thanks, Ian!

 

[emry]

The race team I used to work for used Elf on race days. It was $60.00 a liter. Ooch. It was worth about 3 Hp (dyno) over the standard race gas; at the time F&L and later NuTech. Running the Elf did require a rejet of about two main jet sizes and a little igntion remapping though, and this is where the extra Hp comes from.