AV Fuel

[wyatt emp]

I started a post about giving my 10' single a little more power. Reading through other threads about fuel I see several suggestions to use Avation Fuel. Is this safe?

[Chris Haynes]

100 octane would be OK in a modern machine. I used to run it in my '82 FXR. It would probably burn the valves out of an old machine.

[wyatt emp]

I thought you were just kidding when you suggested it on earlyer thread about a boost to my 10', but then reading other threads about fuel many have suggested AV fuel. Some claim to be running straight, one guy put 1 pint per gallon, and one guy added Marvel Oil to his. I had gotten into a Model T cite years ago when I first got my T trying to learn but like here everyone seem to have their own opinion and secret fuel formulas. One guy wouldsay use this or that and another would say "what ever you do don't use that" Interesting. Looks like I have some lab work to do............

[exeric]

As our friend Indianut says; "you're wasting you money putting high test in a flathead". I run regular in my I.O.E.s and flatheads and have no complaints, however, you should look into finding a source for non-ethenol gas.

[c.o.]

This topic has got me to thinking about fuel quality back in 1910. It seems to me that in articles I have read that the gasoline wasn't always the best (cut with kersosene, etc.) These bikes were built to run on this stuff. I don't know if trying to get the best quality is going to do much good. Eric's quote from Indianut rang true when I had my 45 parked at the pump. I'd hit the low grade button and it loved it...

[kg993]

A high oct. fuel won't benefit a low compression motor. Hate to say it but lead would do the most good. And like it was said before stay ethanol free.
Kerry Glaze

[bmh]

Back before the great wars gasoline was just that.... gasoline. Not the high octane witches brew we grew up knowing that contains 60% or less actual "gasoline" and a host of other distillates ( benzene & toluene being the major two). Straight run gasoline has an octane rating of about 50. Modern gas was developed to fuel aircraft during the world wars and the benefits were passed on to us. That's why compression ratios are so low on early machines, not enough octane to run higher ratios. As for 100LL (blue Avgas) we used to cut it 50/50 with super unleaded for use in our street bikes. This was to avoid the need to re-jet the carb and avoid the possibility of burning a valve or frying the pistons.

[t-jacobs]

Where do you find Ethanal free gas? I suspect the Ethanal is the reason why I have trouble with my weedeater, chain saw and leaf blower. All of which ran great for years untill recently.

[kg993]

http://www.pure-gas.org/index.jsp?stateprov=TX

This may be a start.

Kerry

[micmac]

It ain't a bike, but when I fill up my 63 Chev pickup for those Sunday rides in cool weather, I put that fuel additive in or it dosen't run good. I forget the brand name, I think it's made ny Gunk? I think the composition of gas has changed even since the early 60's.

[junkyarddog]

I used an octane booster for a season or 2 in the late 70's. Especialy my XLCR would have a heavy ping if I lugged it at all.
I believe it was 104 octane booster. The bikes ran a lot better with it, but when I tore my 93" Sindwinder down the pistons looked like they had acme. They were not scored at all and could have been run again, but I was changing to higher compression forged pistons anyway. I thought the booster was causing it so I quit using it and started using about 25% Cam 2 racing fuel for octane and the lead. Now I run Aviation gas, it is a lot cheaper.
I use the Av gas in my 68 Shovel as much as possible. When I am leaving for a ride I fill with 100% av gas and then have to use pump gas until I get home. The inside of the pipes are a light grey and the motor loves it.
I have run a mixture in my 45 UL and have noticed no problem.
Jim

[t-jacobs]

Thanks KG993,

I found a station two miles from me on the wesite you posted, but someone commented that they took some of the gas home and tested it and found Ethanol. I do not see a email addres or a way to contact this person. I am curious how someone can test for ethanol in gas at home.

[yhprum]

There is a simple test. You take a jar, put about 1/2 gasolene in it. Slowly pour in some water so as to see where the separation point is. Mark it on the jar. put a lid on the jar and shake it around for a minute or two. Let it sit for awhile. If there is no ethanol, the separation point will be in the same location. If there is ethanol in the fuel, the water will absorb it and it will apear that there is more water in the jar.

Steve

[t-jacobs]

Thanks Steve,

I didn't think it would be so simple. I expected some expensive test kit with chemicals would be the answer.

[bmh]

Another thing to consider.... Is the gas in your area the re-formulated??? The additive package in re-formulated gasoline is supposed to help keep the gas from evaporating and ruining the whole planet. This also makes it work far worse in a carburetor, of course modern high pressure fuel injection doesn't really care. If an additive helps, that's great. I've been looking into fuel additives here the past few months and it seems that most are not much more than pure naphtha at a standard prescribed rate of 1oz. to 2.5 gals. At $10 a gallon, naphtha is a lot cheaper than stabil or whatever.