XtremeAir125

Member
Jul 5, 2001
120
0
i usually run 93 octane fuel in my tank, but i wanna try jet fuel (aviation gas), id like to find race fuel but i live in maine and don't have a clue on where to buy it. so would jet fuel make any difference or is just a waste of money? one way to find out right?
 

Layton

~SPONSOR~
Aug 2, 2000
898
0
Well, jet fuel would be bad because it is basicly kerosene and wouldn't even burn in your engine.

Do a search on aviation fuel. There has been many discussions about this on this site.

Good luck!:)
 

holyroller1

Member
Jun 20, 2001
180
0
As Layton pointed out jet fuel and aviation gas are 2 different things. Jet fuel being basically kerosene. You would NOT want to use jet fuel for certain. Av gas I believe can be a suitable substitute. You may however want to look into specially made race gas. Brands like VP are very good IMO. I currently use a 50/50 mix of VP C-12 and 93 octane Mobil. The bike has much better throttle response and the jetting was much easier to get down. I did have to jet leaner both the slow jet and main YMMV.

Good luck and as Layton said, do a search. There are several valuable topics along this line.
 

IBWFO

Member
Aug 5, 2001
367
0
Av gas is NOT good for your bike. I'm no expert and maybe some that are will reply. Av gas in my understanding is for high altitudes and constant speed.
Stick with VP.
Regards
 

holyroller1

Member
Jun 20, 2001
180
0
IBWFO

Why do you say it is not good for a bike. You may lose throttle response, but I don't think it will hurt the engine, assuming proper jetting of course. Not any more than regular pump fuel will anyway:). I have used Av gas in the past with no adverse effects to my engine. Did it work as well as the VP? No. But it did not hurt anything.

I would be interested to know why you think it is not good for your bike. Where did you find this info. Keep in mind, lack of performance and destructive are 2 entirely different characteristics.
 
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R White

Member
Sep 13, 2001
141
0
I.ve used av.gas in my harley for yrs just one thing mix it 50%/50%with pumpgas, it will work just fine that way av.gas has an average octain of 102-125 it just more refined than pump and right know hard to buy you need to know the gas man @ your local airport! :eek: :( :( :( :(
 
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IBWFO

Member
Aug 5, 2001
367
0
I talked with some of the guys @ Pro Circuit. They said without going into specifics that the make-up of AVGAS was not good for todays typical 2 strokes.
I also remember reading in one of the dirt rags that it was not good either.
You run whatever you want, it's your bike.
Regards:cool:
 

keith500r

Member
Jul 27, 2001
261
0
Im kind of curious why so many people want something better than pump gas. If you want more power, get a better bike or modify the engine. I understand if your bike requires high octane gas due to compression ratios.. but if you dont need it why would you want to increase the operating cost of your bike? I think running a modern 2 stroke costs enuff as it is.
 

R White

Member
Sep 13, 2001
141
0
I.ve never run av.gas in two stroke but for thumpers its fine, all private planes have is basicly a hi output vw bug eng! and in fact thats what some use !!!! also remember the guys at dirt rider mag.have sponsers,ie. pay there salaries
 

IBWFO

Member
Aug 5, 2001
367
0
This is a paragraph that Rich wrote on "GAS"

This all brings us back to the octane question : How much do you need. We'll go into more detail in Part II of the series but here are a few suggestions to get you started:

Start simple and work your way up. Try a good grade of premium gas that doesn't contain ANY ALCOHOL. In most states they will have a sign on the side of the pump warning you about the percentage of alcohol (ethanol or methanol) in the fuel. Most well modified normally aspirated engines can run on 95 -100 octane gasoline. Good porting with flow matched transfer ports can significantly lower octane requirement on two cycle engines. If your engine detonates try one (or all) of the measures to lower the octane requirement of the engine. If all these measures fail, try mixing pump gas 50/50 with a good of good quality race gas (Phillips 66, Power Mist, UNION 76, Sunoco, VP, ELF, etc..) with your gasoline. Make sure you use race gas specifically designed for you your type of application. The fuel manufacturers can make recommendations based on your engines rpm range, bore size, and the type of riding you'll be doing. It's best to stay away from AvGas for your bike. We'll go into the specifics of AvGas in the next installment. Keep in mind that octane requirement is lower at high altitude and high humidity. An engine that ran fine at 10,000 feet could very easily detonate at sea-level, or a sudden drop in humidity on a hot day can cause knocking that never appeared before.

Like I said, I's YOUR bike run what you want.
For some reason I trust Mitch Payton?
Regards
 

holyroller1

Member
Jun 20, 2001
180
0
IBFWO:

So you are saying that mitch payton stated that Avgas will damage your engine more than pump if it is correctly jetted? I would like to know in detail why. Not just say because it's so. I am not saying you are wrong, but I do want facts and quotes not speculation or hearsay.

As I stated in my first post a specially formulated race fuel is the suggested way to go. However just because Avgas may not perform as well as a "race fuel" does not necessarily mean it will damage your engine, which you have implied.

Just because something is not recommended over something does not mean it will "be bad for your bike". This is what I want to clear up.

And no where did I see in any of Rich's posts did he say Avgas run correctly will damage your engine. He mentions pore throttle response, etc... but not damage. Even suggests mixing race fuel and Avgas as an alternative.
 

IBWFO

Member
Aug 5, 2001
367
0
This seems futile. I have been told and have read that it is not good to run AVGAS. I do not nor will not run it in any of my bikes. I'm no "chemist" and obviously can't give you the quality answers you need.
Suffice to say it's YOUR choice!
Regards
 

Jamir

I come and go
Aug 7, 2001
1,939
0
Number one, jet fuel and Avgas are two different things. Do not use jet fuel for anything but jets! Avgas is engineered for constant RPM's at high altitudes, which is the exact opposite of what your bike needs. Your best option would be 92/93 octane pump gas.
 

Dirty Dave

Sponsoring Member
Jul 31, 1999
216
0
95336
Just my $.02: the most common "jet fuel" used in USAF jet powered acft today is called JP8. It is basically a very good grade of diesel fuel. They use it in all the diesel powered equipment(generators, compressors and such...)
AvGas is generally only available in lowlead 100(octane) The old leaded 115/145 is rare these days. As far as using it in your bike, unless you had the extra(excessive) cylinder compression/advanced ignition timing to take advantage of its octane attributes, why waste you $$$.:confused: Kinda' like putting premium pump gas in a stock Honda civic :silly:
Oh OK... so it was my $.03
 

SndyRds

LIFETIME SPONSOR
Feb 1, 2001
110
0
Aircraft engines run at very slow RPM's, Typically 4,000 is a high power setting for a general aviation aircraft. Avgas is made for steady power settings and low speeds, it made to burn with a slow flame front and consistancy. The added octane in Avgas is negligable, you'd be happier with Race gas. I've read alot about this over the years. I've been riding for about 27 years and an aircraft mechanic for 14 years. Also most aircraft cruise at about 2,500 RPM this is not the same enviornment as your motercycle.
FWIW Id go with the jet fuel if your running a turbine (not turbo). Just kidding. People rave about Avgas all the time, I think it's a placebo effect.
 

holyroller1

Member
Jun 20, 2001
180
0
Originally posted by SndyRds
Aircraft engines run at very slow RPM's, Typically 4,000 is a high power setting for a general aviation aircraft. Avgas is made for steady power settings and low speeds, it made to burn with a slow flame front and consistancy. The added octane in Avgas is negligable, you'd be happier with Race gas. I've read alot about this over the years. I've been riding for about 27 years and an aircraft mechanic for 14 years. Also most aircraft cruise at about 2,500 RPM this is not the same enviornment as your motercycle.
FWIW Id go with the jet fuel if your running a turbine (not turbo). Just kidding. People rave about Avgas all the time, I think it's a placebo effect.

You are absolutely correct.

What I take issue with is people saying that it will damage your engine if you use it. That is just utterly false.

Here is what Rich had to say about the issue:

"AVGAS isn't the best choice but it certainly won't damage anything in an engine."

I'll stick with my 50/50 C-12 and Mobil 93 octane.
 
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