Avgas?

TerryB
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TerryB
Edited Date/Time 11/5/2015 2:59pm
I know this has been discussed before, and I've heard differing opinions. Why should or shouldn't I run avgas in my bike? Two-stroke? Four-stroke? I really don't have a problem running pump gas, but I have to drive 20 miles just to find 91 without ethanol, while I can get avgas about 8 miles away.

Any knowledgable input would be appreciated.
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zjbell
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zjbell 4/19/2008 11:58am
4/19/2008 11:58am
It's likely 100LL.

All I've ever been told about 100LL is that the lead prevents knocking which extends the life of aircraft engines. I would think it's similar to a lead based racing fuel.
harescrambled 4/19/2008 12:08pm
4/19/2008 12:08pm
You shouldn't run avgas in a bike because your carb/injection isn't set up for it. It has a different specific gravity than pump gas or race gas, and it also has a different set of additives.
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500 Mike
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500 Mike 4/19/2008 12:47pm
4/19/2008 12:47pm
It's made to run well at high altitude. If you are riding at 15,000 ft elevation then it's probably a good thing to use.
TerryB
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TerryB 4/19/2008 1:08pm
4/19/2008 1:08pm
Well I guess I'll continue making that 20 mile drive for non-oxy 91 then.

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Scotty
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Scotty 4/19/2008 1:32pm
4/19/2008 1:32pm
All of that stuff is exaggerated.. When I used to ride 2 strokes, I ran straight Avgas all of the time and the never had any negative effects.. Im not to sure about 4 strokes, but 2 strokes I would run that stuff all day long!
70sSuperstar
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70sSuperstar 4/19/2008 3:15pm
4/19/2008 3:15pm
never had any problems here. when i was younger i ran modified cylinders and heads, about 230 cranking pounds and needed the slower burn, avgas was cheap and worked. as for now, stock engines, 93 pump fuel 50:1 mix and im ready to go. at fifty years old 1st or 41st i care less, just want to hang out and have fun!!!
BobbyM
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BobbyM 4/19/2008 4:06pm
4/19/2008 4:06pm
avgas myths continue...
madmaxperformance 4/19/2008 4:06pm
4/19/2008 4:06pm
Frikk, this is one debate that pisses me off. Look, Cessnas dont run at 15,000 feet! AVGAS IS GREAT FUEL!! If you want, buy some AV, and blend it 50/50 with regular pump gas. I build two stroke engines, and had a business building snowmobile engines for multiple years. We ran it on the dyno, and in the mountains, and on the lakes. We ran it in the race bikes, ( rank 250s and strung out 125s.) It is GREAT fuel!!! VP salesmen will tell you different, and we ran that too. It was great fuel too. But to say AV gas isnt good fuel, is uneducated guessing. 100LL is excellent.
Its not "DRY" its not bad, its not lower power, its not slow buring.... get over it!

So, short answer to your original question. Av is just fine. Mix it 50/50 with regular pump gas, and you will be very happy.
Scotty
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Scotty 4/19/2008 5:03pm
4/19/2008 5:03pm
madmaxperformance wrote:
Frikk, this is one debate that pisses me off. Look, Cessnas dont run at 15,000 feet! AVGAS IS GREAT FUEL!! If you want, buy some AV...
Frikk, this is one debate that pisses me off. Look, Cessnas dont run at 15,000 feet! AVGAS IS GREAT FUEL!! If you want, buy some AV, and blend it 50/50 with regular pump gas. I build two stroke engines, and had a business building snowmobile engines for multiple years. We ran it on the dyno, and in the mountains, and on the lakes. We ran it in the race bikes, ( rank 250s and strung out 125s.) It is GREAT fuel!!! VP salesmen will tell you different, and we ran that too. It was great fuel too. But to say AV gas isnt good fuel, is uneducated guessing. 100LL is excellent.
Its not "DRY" its not bad, its not lower power, its not slow buring.... get over it!

So, short answer to your original question. Av is just fine. Mix it 50/50 with regular pump gas, and you will be very happy.
Great post! The altitude excuse is a joke. Run it!
harescrambled 4/19/2008 5:25pm
4/19/2008 5:25pm
madmaxperformance wrote:
Frikk, this is one debate that pisses me off. Look, Cessnas dont run at 15,000 feet! AVGAS IS GREAT FUEL!! If you want, buy some AV...
Frikk, this is one debate that pisses me off. Look, Cessnas dont run at 15,000 feet! AVGAS IS GREAT FUEL!! If you want, buy some AV, and blend it 50/50 with regular pump gas. I build two stroke engines, and had a business building snowmobile engines for multiple years. We ran it on the dyno, and in the mountains, and on the lakes. We ran it in the race bikes, ( rank 250s and strung out 125s.) It is GREAT fuel!!! VP salesmen will tell you different, and we ran that too. It was great fuel too. But to say AV gas isnt good fuel, is uneducated guessing. 100LL is excellent.
Its not "DRY" its not bad, its not lower power, its not slow buring.... get over it!

So, short answer to your original question. Av is just fine. Mix it 50/50 with regular pump gas, and you will be very happy.
I never said avgas wasn't good fuel.All I said was it's different than pump gas, which is reason enough for me not to run it.
tunedlength
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tunedlength 4/19/2008 5:29pm
4/19/2008 5:29pm
Av 100LL is very good fuel.
Ran a watercraft team back in the days when there was almost no limit to the mods. two cylinder two stroke engines under full load for 20 minute races.
We were sponsored by a race gas company that made the worst fuel (for this application) possible.
The truth is we did not use the fuel we could get for free, we used 100LL.
About half of the races were at the ocean so the high altitude thing is complete B.S.
Last time I checked all of our beach races were at sea level. Nothing funny in this fuel just a very high quality fuel.
CR500Rider
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CR500Rider 4/19/2008 6:31pm
4/19/2008 6:31pm Edited Date/Time 4/16/2016 6:39pm
We ran AV gas in seriously modified 80's & 100's back in the day with zero failures.
zjbell
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zjbell 4/19/2008 7:14pm
4/19/2008 7:14pm
Mixture is controlled by the pilot in light piston airplanes, some of the most demanding periods of engine use can occur near sea level.
Racer92
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Racer92 4/21/2008 9:16am
4/21/2008 9:16am
I ran avgas and got carb ice.

Dammit.

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jay_547
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jay_547 4/21/2008 9:28am
4/21/2008 9:28am
just curious, how much is the stuff compared to pump 91 or race gas?
FLvet
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FLvet 4/21/2008 9:31am
4/21/2008 9:31am
Get some good leaded Sunoco at your nearest drag strip.
Adam43
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Adam43 4/21/2008 9:42am
4/21/2008 9:42am
It is an excellent fuel, especially considering the price you can typically find it at. I don't use it in my stock-ish 450...pump is fine there, and its not the type of fuel that adds power.

But I have used it in my modded 250 2strokes for years. You can run much higher compression and wilder ignition timing and it will live just fine on the AVgas. I just laugh at all the fools who would tell you otherwise. The idea that it somehow isn't high quality is just assinine. Its just not neccessary for stock bikes, that's all.
Big Lenny
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Big Lenny 4/21/2008 9:51am
4/21/2008 9:51am
Got a friend who was running it, his shit is sitting in the garage as we speak,..Broken..

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TerryB
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TerryB 4/21/2008 9:54am
4/21/2008 9:54am Edited Date/Time 4/16/2016 6:40pm
The non-ethanol 91 costs me around $3.70+ per gallon, and it costs me a couple of gallons to get there. I'm not sure how much the avgas is, I haven't looked further than, if I can burn it without suffering performance loss or reliability issues. I assume It's comparable in price to the B32 I can get in town,. but I don't want to burn that in my stock compression two-strokes anyway.

Thank you for the informative posts. I think I'm going to try some. What is the going rate for avgas? I imagine around 5 or 6 bucks?

FLvet, no drag strips around here. They tried to open one two years ago and people freaked out.


edit: I just looked up the local airport website. They've got 100LL listen at $3.99 but it hasn't been updated since March 22nd. At that price, I'd run it undiluted if it's not too much for stock compression.
partialperson
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partialperson 4/21/2008 10:40am
4/21/2008 10:40am Edited Date/Time 4/16/2016 6:40pm
I've been running it in my sons MX bikes for 10 years, NO PROBLEMS! We currently run a 250t & 250f. I ran it in my highly modded strip/street KZ1000 for years before that, NO PROBLEMS! Race Fuel dealers will tell you not to run it for various reasons. I was in the race fuel business in the 70's, benzyne & methanol, I have found no detrimental side effects from running AvGas.
partialperson
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partialperson 4/21/2008 10:45am
4/21/2008 10:45am Edited Date/Time 4/16/2016 6:40pm
Madmaxperformance, are you the same madmax that worked for 2stroke guru Paul Gast & later involved in the high performance jetski engine programs?
CamP
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CamP 4/21/2008 11:09am
4/21/2008 11:09am Edited Date/Time 4/21/2008 11:12am
100LL is better fuel than pump premium with 10% Ethanol. My closest gas station with non-ethanol gas is 25 miles away but it's only a few miles from my track so I get gas there on my way to the track.I wouldn't hesitate to run 100LL if it was more convenient.
rubarb
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rubarb 4/21/2008 11:21am
4/21/2008 11:21am
TerryB wrote:
I know this has been discussed before, and I've heard differing opinions. Why should or shouldn't I run avgas in my bike? Two-stroke? Four-stroke? I really...
I know this has been discussed before, and I've heard differing opinions. Why should or shouldn't I run avgas in my bike? Two-stroke? Four-stroke? I really don't have a problem running pump gas, but I have to drive 20 miles just to find 91 without ethanol, while I can get avgas about 8 miles away.

Any knowledgable input would be appreciated.
Log off and never come back.
Tiki
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Tiki 4/21/2008 11:37am
4/21/2008 11:37am
Do you have shorter motos running AV gas over pump? If the answer is no, dont change.
SEEMEFIRST
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SEEMEFIRST 4/21/2008 12:48pm
4/21/2008 12:48pm
Ethanol sucks!!!
I'm sitting here looking at a piston that looks like it spent the summer sitting in salt water thanks to that shit.

High compression+ethanol (even 10%) = death by detonation.
todder
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todder 4/21/2008 1:58pm
4/21/2008 1:58pm
We ran it for years with mod sled engines, no problems.
Tiki
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Tiki 4/21/2008 2:17pm
4/21/2008 2:17pm
SEEMEFIRST wrote:
Ethanol sucks!!! I'm sitting here looking at a piston that looks like it spent the summer sitting in salt water thanks to that shit. High compression+ethanol...
Ethanol sucks!!!
I'm sitting here looking at a piston that looks like it spent the summer sitting in salt water thanks to that shit.

High compression+ethanol (even 10%) = death by detonation.
I wonder how much geography plays a part.
xnationalwrench 4/21/2008 2:26pm
4/21/2008 2:26pm
Terry,
look at VP RACING FUEL web site and see if there is a dealer close by some of their racing fuel are semi reasonable and your bike will thank you for it.
CR500Rider
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CR500Rider 4/21/2008 2:47pm
4/21/2008 2:47pm
Big Lenny wrote:
Got a friend who was running it, his shit is sitting in the garage as we speak,..Broken..
Is your friends bike a 4 stroke? I can't comment on running AV gas in a 4 stroke but like I said, we ran it for years in some highly modified bikes with ZERO failures. That was multiple motos on Sunday, practicing all week on my track, repeat the next week, ZERO failures. Frames were another story. Do I run it now? No, because the CR500 runs fine on pump gas. The CR125 is almost back together and it will run on 100LL if it pings on pump gas. No worries here about using AV fuel.
zjbell
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zjbell 4/21/2008 2:59pm
4/21/2008 2:59pm
Racer92 wrote:
I ran avgas and got carb ice.

Dammit.

Whistling
carb heat! carb heat!

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