is aviation fuel good to run in a 450R? what besides octaine and price is the difference from 91 unleaded?

Before I used the internet as a tool a lot of people told me that I could use Avaitoin fuel in my 416ex, but I did some research, and the word of mouth on exriders... "dont know if that is saying much" its bad for the bike it leaves a trace behind.

I know several people who has use avaiation gas mixxed with 93 octane, and they had no problem......


I dont know why avaition gas is bad on the internet, but works in the real world?? I might be missing something..

but i witness first hand several bikes with high compression pistons running off av fuel.

I get the same impression on av gas I see alot of people running it in there bikes like trindy raptor and few banshees around here but I tell them that I run 110 VP and it cost 40 buck for 5 gallons and they laugh
but some people on the net swar it not good to run
I would like to see some down to earth info on why its bad because now its cheaper than pump 93

ABOUT AVIATION FUELS - Aviation gasoline (or "av gas") is blended specifically for use in small aircraft. It's also commonly used by many high performance engine owners because of it's high stated octane rating (usually 100-110) and the relatively low price compared to racing fuel. Unfortunately this fuel is not all it appears to be. Av gas octane is rated on a different scale than gasolines intended for ground level use. What is 100 octane "av", is not necessarily 100 octane "ground level". Besides this, there is also a big chemical difference. Normal ground level race fuels are made up of gas molecules that have a "light end" and a "heavy end". The light end of the molecule ignites easily and burns quickly with a low temperature flame (as a piece of thin newspaper would burn). The heavy end of the molecule is not so easily ignited, but it burns with a much more intense heat (as an oak log would). This heavy end of the gasoline molecule is responsible for the hotter, more powerful part of the combustion process.

Small aircraft are constructed as very weight conscious vehicles. That's because their somewhat weak engines often have difficulty taking off with any extra weight. To help reduce this weight problem, av gasolines are blended with no heavy molecule end. This makes a gallon of av gas weigh substantially less than a gallon of ground level fuel. Since small plane engines turn very low rpms and produce so little power, the omission of the heavy end is not a horsepower issue. However, for high output pwc racing engines, there is defiantly a compromise in power. This, despite the fact that many pwc owners experience the desirable cooler operating temperatures that "av" gas offers. In addition, some blends of av gas will quickly separate from some oils used in premix situations. For the above reasons, we do not recommend the ongoing use of 100% av gas, and we will not prepare any "av gas" engine kits.

Despite all this bad news, running av gas (accepting the slight power loss) is usually a better choice than

burning down a high output engine on regular pump gas. In this situation, the best choice is usually a 50/50 mix of pump and av gas. That provides "some" heavy molecule ends for the engine.

http://www.groupk.com/gas.html

and again people still run av gas with no problems...


so the only downfall to av gas is that you may not get as much hp because it has no heavy molecules?

Do a quick search guys and you will find all the info you could ever need on AV gas. It has been discussed on here many many times.

good topic. I have no reason to use av-gas in my 450R, but ran several tanks of av-gas premixed in my 240 Blaster(about 11 yrs ago if memory serves) when my dad was in the process of restoring his biplane. I really didnt notice any difference in performance or any of that jive but Its cool to have teh differences explained cuz I dint know.

Eric Gorr's thoughts

Fuel for thought

so far after doing some research the worse thing can happen is slugish throttle response?

and it can help prevent detanation???

and its cheaper than race fuel


i believe all of these horror stories are out so people like us wouldn't run av fuel so it wouldnt be such a demand on av fuel to keep the prices low....


who knows

It may be less "crisp" than race gas. I'm not sure if it's the lack of heavy versus light molecules are work, or the addition of other gasoline additives like oxygenates that may provide more power if more fuel is fed to the engine. The fact is that I don't know. However, many have reported that race fuel is peppier.

The level of TEL (lead) clearly inhibits detonation. TEL is the most effective chemical found to slow the flame front down. To fast a burn is largely what causes detonation.

The benefit of avgas is cost and that it allows you to run higher compression ratios than are possible with auto fuel. Higher compressions equals more power.

One thing that may be an issue is jetting. Your jetting requirements may vary by the type of fuel you use. Find the fuel you want to run, then jet to the fuel. Jumping back and forth with fuels without adjusting jetting will result in uneven and unpredictable power output.

If you run a rich enough mixture you will also slow the flame front down. However, at some point beyond the best power mixture you will be wasting fuel and having lower power output. So, 93 octane auto fuel might work in a high compression engine if the mixture is rich enough, but the results would be counter productive.

Nonsense, octane is measure on the ground just like motor fuels. This is important because rated octane must be available on take off where max power is being produced and the chances for detonation are greatest.



I have no idea where that comes from. Gasoline is going to weigh roughly 6 lbs per gallon regardless of formulation. Sure, if you blended massive amounts of alcohol in the fuel it would be marginally lighter, but not enough to be significant. Also, refiners cannot place alcohol in avgas.

I don't understand where all these mystical properties for avgas come from. Internet exageration I suppose by folks that don't know.

DOES AV GAS WEAR OUT RUBBER OR PARTS IN THE CARB???

I have ran AV gas in alot of my stuff for over 10-15 yrs..including 68 Camaro,Banshee.multiple CR's,lawnmowers,generators ect,LOL
no really It works great!! Dont get me wrong I also buy a fair share of race gas in the 55 gl drums ...But I always seems to be at the airport filling multiple jugs before dragracing night....Pump gas sucks!!! AV gas is not much more than super unleaded..runs better,cleaner,reduced detonation.and smells damn good..lol and wont leave the black crappy soot in your exhaust...nice light gray color like race gas..MY OPINION
i will never run pump gas in any of my toys!!! only for cars!! But depending on your engine set up.compression? you may need RACE GAS?? but for mild built or stock GO FOR IT.....Late

Aviation fuel is NOT designed to perform in a typical automotive style engine....

It will burn....yes, and yes, SOME does have more octane....but dont confuse the octane 'rating' of AvGas to your typical motor fuel..... because they are not the same....

it is true that AvGas is rated for less dense air (higher altitude).... even though 210Driver is correct, and that upon take-off (most critical area for aircraft) is performed at ground level, the AvGas constituants still develop the octane levels of this fuel to be used at a much less dense air mix than a typical auto......even a small trainer aircraft will have a ceiling of close to 10,000 ft.....80/87 or 100/110 fuel (two typical types of Avgas) are rated using different formulas than pump gas..... one of the reasons told to me by someone in the industry of chemical analysis for fuels is this....the load variations of an aircraft do not fluctuate nearly as much as a typical automobile..... even upon Take-Off.... and 210Driver can confirm this.... a typical small aircraft engine is designed to work at a specific RPM level...irregardless of power output.....some small aircraft (piper cubs and small trainers) will not have variable pitch propellers, but a typical high performance retractable geared aircraft such as a '210' or Bonanza that I owned, do. You simply set the RPM level of the engine and 'feather' or alter the pitch of the propeller to control air speed. Yes, you will push the throttle all the way in for initial take-off, but the RPMs will rarely vary more than 200-300rpms....you change the pitch of the propeller to compensate for more power vs more speed. Also, the RPM of an aircraft engine is relatively low compared to your auto.....2800rpm is about average If I remember correctly (its been while since ive flown)....whereas your typical auto will start off at 1000rpm and can race up to 6000 rpm on a typical auto.....and your going from a dead start to high speed constantly and repeatedly under a LOAD....whereas in an aircraft, you take off, you fly at a constant speed/rpm....then you land... thats it... very little variance upon the engine...

AvGas has a lot of additives to reduce heat and maintain its burn qualities, plus all the additives to help disipate WATER, a major issue with aircraft, not to mention the dyes....blue/red etc....(which are also added to some race fuels)....and additives to reduce what we call 'carburetor Icing'....the freezing of fuel along the venturi of the carb....(very bad).....but easy to control with carb heat IF you remember... (long story)

its also a violation of law to dispense Avgas into a container (at least here in Cali)....so many airports will not allow this.....but some, if not closely regulated, really dont care.....


at any rate......yes, ive burned Avgas in my street car way back in the 70's...and yes, it ran fine....but still had stock compression 11:1....NO, Avgas will not destroy rubber or gaskets or the like....most aircraft still flying today are from the 50's/60's/70's....using typical single venturi (barrel) carbs.....after that.. many high performance aircraft went to fuel injection.... and NO, I will not burn Avgas in my R.....


anyways.....use it...dont use it.... its up to you..... jmho....Greg

80/87 and 100/130 are pretty much gone. 100LL is the only aviation gasoline you're likely to find at any airport.

Here's the deal with octane rating and what it means for aviation fuel:

100LL has a minimum MON of 99.5.

That MON rating is generated using the same ASTM D2700 testing standard that other MON ratings are generated from. Within the ASTM D2700 standard is a conversion table to generate the lean mixture rating. That's were the "100" in 100LL comes from. Below around 110 MON the difference between MON and lean mixture rating is generally less than 2 points (only 0.5 points in the case of 100LL).

Aviation gasoline also has a rich mixture rating standard (ASTM D909). It's 130 for 100LL. And it's the second number in 80/87 and 100/130, the first being the lean mixture rating. 100LL was developed as a direct (lower lead) replacement for 100/130, hence the identical octane ratings.

We can ignore the rich mixture rating. It's not applicable to us. Our pump fuels and race fuels have a rich mixture rating too but since it's never tested for that type of rating we have no idea what it is. And that's fine.

Our pump fuels are listed as (RON + MON)/2. RON is generated using the ASTM D2699 testing standards. Most fuels have about a 10 point spread between MON and RON. That means 100LL would have an octane rating of about 105 if you wanted to put it into pump fuel terms (99.5 x 1.05 = ~105).

The easiest thing is to simply use the same octane rating method when comparing fuels. MON is known for most fuels (and the most relevant to us) so that's the easiest one to use. Many racing fuels use MON exclusively. The big exception is that we don't know the MON for pump fuels. But we can estimate by multiplying (R+M)/2 by 0.95.

94 pump fuel = ~ 89 MON
91 pump fuel = ~ 86 MON
100LL = 99.5 MON
Racing fuel = there is so much variation in the types of racing fuels available that it's tough to generalize (e.g. VP110 = 107 MON, VPC12 = 108 MON, VPU4 = 92 MON). You just have to pay attention to the specs to know what you've got.

Thanks for the info..