One of the large car museums in Phoenix that I attended use 100LL in all of their vehicles without any stabilizer. 100LL doesn't degrade like automotive gas. I'm not sure why the goofy extreme measures (argon?) As it isn't needed
Extending life of gasoline by storing under argon
- Thread starter victorforge
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Aviation fuel has a mandated shelf life of ~2 years IIRC. 100LL straight may be too much lead for your engine, and if so you could mix with 94UL or MoGas or whatever unleaded and ethanol free aviation fuel they sell at your local airport. If not, I would just run the 100LL straight, expect to service your plugs more frequently and be careful or do your research before using any synthetic oil. I wouldn't bother with the inert gas blanket.
I run a 100LL/94UL mix on an infrequently used antique boat and only use marine sta-bil for off season storage. Works so far.
I run a 100LL/94UL mix on an infrequently used antique boat and only use marine sta-bil for off season storage. Works so far.
I like the way you think and encourage this.
However, you have a cheaper inert gas available: Exhaust gas! Just pipe the output of your car tailpipe in the "big hole" in your gas can and open the vent hole. (Or get a vent hole kit, tire valve stem, etc.) Set it up a little loose, you won't fit all the engine can breathe through the vent. If there are spark/ flammability concerns maybe fill a trash bag as an intermediate then "squeeze" it out/ in.
This is the whole premise behind EGR systems-- find some "free" inert gas somewhere and use it to displace oxygen, to reduce creation of NOx.
I wonder if there's a jerry can with bladder, like to make it bullet proof or something. The bladder would reduce contact with air/ oxygen.
You're going to "glug" normal air in when the fuel comes out of the can, if you don't have a bladder.
However, you have a cheaper inert gas available: Exhaust gas! Just pipe the output of your car tailpipe in the "big hole" in your gas can and open the vent hole. (Or get a vent hole kit, tire valve stem, etc.) Set it up a little loose, you won't fit all the engine can breathe through the vent. If there are spark/ flammability concerns maybe fill a trash bag as an intermediate then "squeeze" it out/ in.
This is the whole premise behind EGR systems-- find some "free" inert gas somewhere and use it to displace oxygen, to reduce creation of NOx.
I wonder if there's a jerry can with bladder, like to make it bullet proof or something. The bladder would reduce contact with air/ oxygen.
You're going to "glug" normal air in when the fuel comes out of the can, if you don't have a bladder.
I would just fill your fuel containers completely in order to displace most of the air.
If it degrades due to oxygen then you need pull a vacuum on your can to remove all the oxygen.
They sell leaded race gas...
I think I would buy leaded gas, straight up. 100LL has a LOT of lead, it’s only low lead when compared with 145 octane for warbirds.
I understand what you’re trying to do, but because of the variability of lead content, you may not be getting enough, or you might, I suppose be getting too much. If you just buy the racing gasoline, you know it’s a consistent mix.
It would also come in sealed containers which would solve both your stability and valve seat problems at the same time.
I understand what you’re trying to do, but because of the variability of lead content, you may not be getting enough, or you might, I suppose be getting too much. If you just buy the racing gasoline, you know it’s a consistent mix.
It would also come in sealed containers which would solve both your stability and valve seat problems at the same time.
I recognised straight away that the combination of 100LL and owning an BMW R60/6 was about valve seats and protecting them against lead free fuel. Been reading Snowbum by any chance ?
My question would be; have you actually been experiencing valve recession as witnessed by the clearances closing up ? If not why worry about it.
Your original valve seats will be cast iron and unlike BMW's first attempt at new seats, they hold up quite well on unleaded fuel depending on how the bike is used. Valve recession is a temperature dependant effect of micro welding between the valve face and seat. If you are in a hot climate, run hard and long distance at sustained high revs, then the elevated valve temperatures will very likely lead to recession on the cast iron seats. The temperature thing is why it's mainly the exhaust valve seats that suffer. On the other hand, If you are in a cool climate, don't do sustained high revs and mostly potter about then the valve temperatures will be lower and possibly won't suffer valve recession at all. The latter scenario has been my experience with my own cast iron seats. After 18 years of ownership, I've seen no measurable change in the valve clearance between annual service so I simply don't worry about it as they are very likely to outlast me. If you ride hard as in the first scenario then you probably do need to do something.
Besides engine revs and load, you can throw in correct ignition timing and fuel mixture as other factors to keep running temperature under control i.e. don't be tempted to retard the ignition or run the mixture too weak.
My question would be; have you actually been experiencing valve recession as witnessed by the clearances closing up ? If not why worry about it.
Your original valve seats will be cast iron and unlike BMW's first attempt at new seats, they hold up quite well on unleaded fuel depending on how the bike is used. Valve recession is a temperature dependant effect of micro welding between the valve face and seat. If you are in a hot climate, run hard and long distance at sustained high revs, then the elevated valve temperatures will very likely lead to recession on the cast iron seats. The temperature thing is why it's mainly the exhaust valve seats that suffer. On the other hand, If you are in a cool climate, don't do sustained high revs and mostly potter about then the valve temperatures will be lower and possibly won't suffer valve recession at all. The latter scenario has been my experience with my own cast iron seats. After 18 years of ownership, I've seen no measurable change in the valve clearance between annual service so I simply don't worry about it as they are very likely to outlast me. If you ride hard as in the first scenario then you probably do need to do something.
Besides engine revs and load, you can throw in correct ignition timing and fuel mixture as other factors to keep running temperature under control i.e. don't be tempted to retard the ignition or run the mixture too weak.
Only issue I can think of is the high octane most race gases have.
These look fairly reasonable though:
93 octane: https://vpracingfuels.com/wp-content/uploads/2019/12/MR12-Spec-Sheets_100419A-1.pdf
98 octane: https://vpracingfuels.com/product/motorsport-98l-ms98l/?c=217&
Here is what Sunoco recommends for vintage cars:
www.sunocoracefuels.com
Reckon it would work for vintage bikes as well.
Storing Vintage, Collector, and Muscle Cars
www.sunocoracefuels.com
Reckon it would work for vintage bikes as well.
Not the same.
I was going to mix a few ounces of 100LL with every gallon of 93 octane from my local gas station. It should be enough to protect the valve seats but not enough to cause any fouling.
$20+/gal vs $8/gal ....
Yes, I got the idea from Snowbaum. The motorcycle has very very low miles on it. I hear from some they experienced issues early on and others with none at all. Figured if it's not hurting anything, better safe than sorry.
I already have a cheap inert gas available. Argon from my welder.
If you read everything that Snowbum has to say about valve recession (which I know is a challenge) the really bad valve seats were BMW's first attempt at a solution in 1981. They made them from a material that a had a poor heat transfer coefficient which effectively made the problem worse not better. Yours are way prior to that date so will still be cast iron.
What Snowbum also points out is the larger capacity 1000 cc engines are worst affected which ties into fact that the problem is temperature related. I have the smallest airhead engine at 473cc and give or take a couple of barrel fins it has the same cooling surface area as the 1000 cc models with the result that it runs relatively cool. No real surprise then that I don't appear to suffer any valve recession at all. At 600cc you have the next smallest engine which should bode well.
On an unrelated topic do you have any problem with pinging ?
The R60/6 had milder cams which means the valves close a little earlier on the compression stroke. Published compression ratios are based on swept volume but in reality dynamic compression doesn't start until the inlet valve is closed. The end result is that engines with the milder cams have a higher dynamic compression ratio at low revs. This has made the R60 slash models a little more prone to pinging. If you should have this problem the usual solution has been to fit a a cylinder base plate to lower the compression.
It depends on what you consider a lot of lead. Pre 1974 regular leaded automotive gasoline had the same amount of lead in it (about 2 grams of lead/gal), and some premium leaded gasoline brands had over twice as much (up to 4.5 grams of lead/gal, but typically about 2.8). 100LL will not contain too much lead for an antique motorcycle as it contains about the same amount of lead as gas that was sold at the pumps back in the day.
Graph of the average lead concentration in premium and regular grades of automotive gasoline from 1950–1989 in the
United States. Solid line is premium grade; dashed line is regular grade. Data from Shelton et al. (1982); Dickson et al. (1987),
Gibbs (1990) and Kaplan (2003).
As far as the variability of lead content in 100LL is concerned, the amount is tightly controlled by the federal government and it is unlikely to have very much (if any) variation.
The OP doesn't need to store the gas with any kind of inert gas. He should just try to find old-school metal fuel cans that seal well. 100LL can last as long as 8-10 years when stored in air-tight metal gas cans.
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Good to know - all of the OP’s concerns - storage life, valve seat recession, etc. are the same as mine with the Packard.
Given the price of racing fuel (about $80 for a 5 gallon can), 100LL is attractive at a mere $6.00/gallon. Further, the Reid Vapor Pressure of 100LL is likely to be higher than racing fuel, which tends to have a low RVP.
Since the Packard’s Detroit Lubricator Model 51 is an updraft carburetor, atomization is a concern for me in addition to the above.
Atomization may not be as much of a concern for @victorforge - depending on his riding conditions, particularly temperature, and how well those old Bing carburetors are working.
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