50/50 avgas mixed with 95?

Tracktor
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Tracktor 9/12/2019 2:53pm
9/12/2019 2:53pm
Oy, AvGas in and of itself is a great option. However, what octane you should run is a component of engine set up. Run the fuel/octane that matches compression ratio, etc.
I set our engines up to run a 50/50 AV & non-ethanol premium mix. It's easy to get, not too expensive, has decent octane rating and is consistent as I buy from same places every time. Since our bikes are set up for it they run great. But put that same fuel in a high compression engine and it may have problems & in a stocker may lose power.
It's my understanding that the only real "power in a can" is oxygenated stuf but even then your jetting is going to change.

We run the above fuel in TC85, TC105 & a couple of TC125's among other things. Pistons wear great and bikes run stellar............
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ctbale
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ctbale 9/16/2019 1:34pm
9/16/2019 1:34pm Edited Date/Time 9/16/2019 1:43pm
I am an Aircraft Mechanic and raced 2 strokes back in the 70s so you can trust my advice. Smile Its a hassel to get the avgas and your not going to save a bucket of money .... but if I were running 2 strokes today and if my bike detonated on 92 non ethanol I would use race gas or the 50/50 mix of 92clear pump and 100LL, 50/50 mix would be my first choice.
1
Richard Tease II 9/16/2019 2:20pm
9/16/2019 2:20pm
Mixing fuels, getting avgas etc etc, your waisting your time. I've put numerous people onto this stuff who have been suffering pinging (detonation) or want to run avgas or race gas. This is all you need.
Non ethanol pump gas and add this octane booster / fuel stabiliser
https://www.nulon.com.au/products/pro-strength-additives/pro-strength-o…

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dmm698
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dmm698 9/16/2019 3:26pm
9/16/2019 3:26pm Edited Date/Time 9/16/2019 3:29pm
TeamGreen wrote:
Interesting reading: but, it starts out with someone having 95 Oct rated fuel available and then they mix it with AV gas? Seems to me a...
Interesting reading: but, it starts out with someone having 95 Oct rated fuel available and then they mix it with AV gas? Seems to me a good fuel booster like VP's Octanium would do better, be more consistent and "cheaper"...?

Yesterday, I rode Twisted Development's '07 YZ 250 project that was based on a thrashed basket case that Jamie got from Austin Howell...it ran like a champ on the track and on amazing single track out behind Cahuilla...

It was running on VP's T2.
captmoto wrote:
That's the advantage way too many people don't have. Running a bike built by a top tuner and can dyno and jet for the best performance...
That's the advantage way too many people don't have. Running a bike built by a top tuner and can dyno and jet for the best performance. I don't know if OP has tried jetting and or different oils or fuel ratios. Is 95 in NZ the same as our 91? Does the gas have ethanol?
I ran AV gas in my YZ465 and my 05 CR250. 40:1 with Maxima SuperM. Both bikes ran horribly on pump gas. It was night and day difference running avgas in my bikes. I tried 50/50 C12 and pump 91 but could not tell the difference except for paying $70 for 5 gallons of C12. Avgas is about $18 for 5 gallons.
TeamGreen wrote:
Good point. I went on to comment on T2 working on other stock bikes and even my old-school Jet Skis. Octanium is $20 a can and...
Good point.

I went on to comment on T2 working on other stock bikes and even my old-school Jet Skis.

Octanium is $20 a can and I mix it into 10 gallons. The best part is I can do it one gallon (or even less) at a time. It keeps well in the steel can it comes in. I tested it, initially, on a stock RMZ 450 w/ Yosh pipe: it made California pump gas much better and eliminated "pump pop" that the RMZ with a white-plug (map) can get.
used To run 100LL in a yz250 with some head work to fix the squish band and didn’t totally bring all the volume back and it worked well. At 4.25$/gal it was easy to swollow burning 4 gallons of fuel on a practice day. After having cylinder ported and head redone spec’d For straight C12, even getting C12 at 10$ a gallon was tough to swallow + oil. 100LL was the base blend for most race fuel companies for a while if I remember correctly.

I switched to T2 because it’s actually cheaper for me (buying by the drum and keeping a N2 blanket on the fuel so it stays fresh) as I don’t have to add oil. For the same day, just switching C12 to T2 I’m +2 sizes on the main jet, due to oxygenation in the fuel. It makes more power but I feel like I’d be lying if I said it was SUPER noticeable.

I did try 100LL in a Fi 450 once for kicks, no mapping changes, and as to be expected it was noticeably worse than pump.

If you think C12 premixed smells good (I found 100LL to be the same scent), T2 smells heavenly. Could never justify it though if I was paying 70-80$ for 5 gallons though.
354racing
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354racing 9/17/2019 3:28am
9/17/2019 3:28am
I run 50/50 100LL /90 non ethanol to get 95 octane non ethanol.CR250,CRF450,YZ250F.runs crisp and clean in all of them,
Irwinmoto
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Irwinmoto 9/17/2019 4:40am
9/17/2019 4:40am
I normally run a 50/50 AV mix but my main reason for running it is its resistance to breaking down. Had a couple incidents where my local pump gas gummed up my carb in a very short period. Once I literally left it sitting in my garage for 3 weeks (should have drained gas out of carb) and went to go riding and found it had turned to varnish and I damaged the needle and seat taking it apart to clean it. So now I mix AV and pump 91 and have never had an issues with it again. Also tend to fill my small engines (mower, trimmer, pressure washer,etc) with AV for winter storage and they take off great in the spring.
WhatchaWant 9/17/2019 9:54am
9/17/2019 9:54am Edited Date/Time 9/17/2019 10:02am
Richard Tease II wrote:
Mixing fuels, getting avgas etc etc, your waisting your time. I've put numerous people onto this stuff who have been suffering pinging (detonation) or want to...
Mixing fuels, getting avgas etc etc, your waisting your time. I've put numerous people onto this stuff who have been suffering pinging (detonation) or want to run avgas or race gas. This is all you need.
Non ethanol pump gas and add this octane booster / fuel stabiliser
https://www.nulon.com.au/products/pro-strength-additives/pro-strength-o…
This stuff is garbage. It is 80-85% kerosene and 5-15% active ingredient which can be bought pure at a chemical supply.

All anyone has to do is look at the SDS of any race fuel or Av gas to see 100LL is basically a low lead racing fuel.
Same with garbage octane boosters.
Look at the SDS.
The best octane boosters are found in quart and gallon steel cans at any local hardware store or chemical house on the super cheap.

Whoever posted 100LL has all this lead is wrong.
It has about 1/2 the amount of C12 and 1/4 the amount of say C16 or higher. Which is around the same amount as the old 110/130 and 115/145 Avgas.

Fuels SDS is the truth behind the myths.

Fancy labels sell. 4.25 per gallon Av gas is the best thing going for a non ethanol fuel.

Also, Av gas has no deicers. The fuels ingredients having ~ -70 and colder freeze points are automatic deicers just by being gas.

And it's not made for high altitude.
Guess where a plane uses max power and has a max load on the engine?
At sea level during take off.

Same as you when trying to take flight over a triple out of a turn.

For decades, Av gas was the base fuel for many blends of race fuel.

Just read the white paper from Phillip's 66 who sell Av gas, and sold race fuel under the brands Trick, Phillips, Track-Tek etc.


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TeamGreen
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TeamGreen 9/18/2019 3:59pm
9/18/2019 3:59pm
captmoto wrote:
That's the advantage way too many people don't have. Running a bike built by a top tuner and can dyno and jet for the best performance...
That's the advantage way too many people don't have. Running a bike built by a top tuner and can dyno and jet for the best performance. I don't know if OP has tried jetting and or different oils or fuel ratios. Is 95 in NZ the same as our 91? Does the gas have ethanol?
I ran AV gas in my YZ465 and my 05 CR250. 40:1 with Maxima SuperM. Both bikes ran horribly on pump gas. It was night and day difference running avgas in my bikes. I tried 50/50 C12 and pump 91 but could not tell the difference except for paying $70 for 5 gallons of C12. Avgas is about $18 for 5 gallons.
TeamGreen wrote:
Good point. I went on to comment on T2 working on other stock bikes and even my old-school Jet Skis. Octanium is $20 a can and...
Good point.

I went on to comment on T2 working on other stock bikes and even my old-school Jet Skis.

Octanium is $20 a can and I mix it into 10 gallons. The best part is I can do it one gallon (or even less) at a time. It keeps well in the steel can it comes in. I tested it, initially, on a stock RMZ 450 w/ Yosh pipe: it made California pump gas much better and eliminated "pump pop" that the RMZ with a white-plug (map) can get.
dmm698 wrote:
used To run 100LL in a yz250 with some head work to fix the squish band and didn’t totally bring all the volume back and it...
used To run 100LL in a yz250 with some head work to fix the squish band and didn’t totally bring all the volume back and it worked well. At 4.25$/gal it was easy to swollow burning 4 gallons of fuel on a practice day. After having cylinder ported and head redone spec’d For straight C12, even getting C12 at 10$ a gallon was tough to swallow + oil. 100LL was the base blend for most race fuel companies for a while if I remember correctly.

I switched to T2 because it’s actually cheaper for me (buying by the drum and keeping a N2 blanket on the fuel so it stays fresh) as I don’t have to add oil. For the same day, just switching C12 to T2 I’m +2 sizes on the main jet, due to oxygenation in the fuel. It makes more power but I feel like I’d be lying if I said it was SUPER noticeable.

I did try 100LL in a Fi 450 once for kicks, no mapping changes, and as to be expected it was noticeably worse than pump.

If you think C12 premixed smells good (I found 100LL to be the same scent), T2 smells heavenly. Could never justify it though if I was paying 70-80$ for 5 gallons though.
Nice post!
Richard Tease II 9/18/2019 4:15pm
9/18/2019 4:15pm
Richard Tease II wrote:
Mixing fuels, getting avgas etc etc, your waisting your time. I've put numerous people onto this stuff who have been suffering pinging (detonation) or want to...
Mixing fuels, getting avgas etc etc, your waisting your time. I've put numerous people onto this stuff who have been suffering pinging (detonation) or want to run avgas or race gas. This is all you need.
Non ethanol pump gas and add this octane booster / fuel stabiliser
https://www.nulon.com.au/products/pro-strength-additives/pro-strength-o…
WhatchaWant wrote:
This stuff is garbage. It is 80-85% kerosene and 5-15% active ingredient which can be bought pure at a chemical supply. All anyone has to do...
This stuff is garbage. It is 80-85% kerosene and 5-15% active ingredient which can be bought pure at a chemical supply.

All anyone has to do is look at the SDS of any race fuel or Av gas to see 100LL is basically a low lead racing fuel.
Same with garbage octane boosters.
Look at the SDS.
The best octane boosters are found in quart and gallon steel cans at any local hardware store or chemical house on the super cheap.

Whoever posted 100LL has all this lead is wrong.
It has about 1/2 the amount of C12 and 1/4 the amount of say C16 or higher. Which is around the same amount as the old 110/130 and 115/145 Avgas.

Fuels SDS is the truth behind the myths.

Fancy labels sell. 4.25 per gallon Av gas is the best thing going for a non ethanol fuel.

Also, Av gas has no deicers. The fuels ingredients having ~ -70 and colder freeze points are automatic deicers just by being gas.

And it's not made for high altitude.
Guess where a plane uses max power and has a max load on the engine?
At sea level during take off.

Same as you when trying to take flight over a triple out of a turn.

For decades, Av gas was the base fuel for many blends of race fuel.

Just read the white paper from Phillip's 66 who sell Av gas, and sold race fuel under the brands Trick, Phillips, Track-Tek etc.


Have you used it before?
dcg141
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dcg141 9/18/2019 4:18pm
9/18/2019 4:18pm
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead deposits from spark plugs when cars still used leaded fuel. I have never seen that before. It was starting to clog the expansion chamber where it fits into the cylinder. I asked him if he was using pump fuel and he said no but would not tell me what he was using. I was wonder if anyone using AV gas in 2 stokes have even seen power valve issues.
Matt Fisher
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Matt Fisher 9/18/2019 5:05pm
9/18/2019 5:05pm
dcg141 wrote:
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead...
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead deposits from spark plugs when cars still used leaded fuel. I have never seen that before. It was starting to clog the expansion chamber where it fits into the cylinder. I asked him if he was using pump fuel and he said no but would not tell me what he was using. I was wonder if anyone using AV gas in 2 stokes have even seen power valve issues.
Used it for years in everything from 50's to 500's with nary a problem. I've also used it in 4 strokes with no ill effects.
YamahaJT1
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YamahaJT1 9/18/2019 5:15pm
9/18/2019 5:15pm Edited Date/Time 9/18/2019 5:22pm
dcg141 wrote:
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead...
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead deposits from spark plugs when cars still used leaded fuel. I have never seen that before. It was starting to clog the expansion chamber where it fits into the cylinder. I asked him if he was using pump fuel and he said no but would not tell me what he was using. I was wonder if anyone using AV gas in 2 stokes have even seen power valve issues.
100LL now contains no TEL? Please share how you determined this.
WhatchaWant 9/19/2019 10:56am
9/19/2019 10:56am Edited Date/Time 9/19/2019 11:04am
Richard Tease II wrote:
Have you used it before?
Why?
It's a rip after reading the SDS for it. You can buy a gallon of the active ingredient in it for the cost of 1 bottle at a chemical house.

Plus I have zero need to run kerosene.

I tell everyone to read the SDS for any fuel or junk octane boosters and see what you are really buying. Unless super oxygenated race fuel, there is nothing special about race fuel except the amounts of specific ingredients.

The best octane boosters are available where I posted for super cheap. It's just not labeled "octane booster"

Fools buy octane boosters with fancy labels.
1
WhatchaWant 9/19/2019 11:00am
9/19/2019 11:00am Edited Date/Time 9/19/2019 11:06am
dcg141 wrote:
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead...
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead deposits from spark plugs when cars still used leaded fuel. I have never seen that before. It was starting to clog the expansion chamber where it fits into the cylinder. I asked him if he was using pump fuel and he said no but would not tell me what he was using. I was wonder if anyone using AV gas in 2 stokes have even seen power valve issues.
YamahaJT1 wrote:
100LL now contains no TEL? Please share how you determined this.
For the last year I've been running 94 UL Avgas and to date have burned about 200 gallons with 60 gallons just over Labor day.
It cannot be used in all airplanes unless spec'ed by the OEM for use so airports with it still sell 100LL.

It is basically 100LL without the lead. It's not available everywhere but my race engines require 93 Min but the OEM preferred fuel is 100LL.

They run at 8-9K for extended times. Plus it smells yummy and costs 4.25-4.50.


TexasVet
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TexasVet 9/19/2019 6:11pm
9/19/2019 6:11pm
tek14 wrote:
About Avgas: AvGas is short for Aviation Gasoline. AvGas is of interest to motoring enthusiasts because of its availability, octane rating and low price compared to...
About Avgas:

AvGas is short for Aviation Gasoline. AvGas is of interest to motoring enthusiasts because of its availability, octane rating and low price compared to commercial race fuels. AvGas might seem an obvious choice but closer study raises some doubt.

AvGas LL100 stands for "Low Lead 100 Octane". TEL (Tetra-ethyl-lead) is added to raise the octane. When used in a motor vehicle this fuel will leave a lot of lead deposits in the motor. 100LL has a high lead content (0.5 grams per litre), even higher than leaded race fuels. The deposits left when TEL(lead) is burned are corrosive and damaging to valves, valve guides, valve seats and cylinder heads. Lead deposits will also block oxygen(lambda) sensors and catalytic converters and foul spark plugs even after only a short use. Also, 100LL has a chemical package added to make it perform at high altitude, and that isn't the best thing for motor vehicle performance here on the ground.

AvGas is blended for large-bore, long-stroke, low RPM engines which run at high altitude. While AvGas' higher octane is useful, smaller-bore, shorter-stroke, high RPM engines will perform better on racing fuel or high quality octane boosters. AvGas has lower volatility so when used in proportions higher than about 40%, part-throttle drivability and cold starts may be compromised. AvGas has a lower specific gravity so it will require a change in air-fuel ratio calibration for the engine to perform at its best. LL100 is blended with a high percentage of aromatics causing reduced throttle response which is not an issue with an aircraft engine but certainly an issue in a high-performance automotive engine. These high levels of aromatics will also damage rubber components in automotive fuel systems such as fuel lines, fuel pump seals and injector washers.

While trying to be as respectful as possible(to the folks who quit reading it), a lot of folks quit reading your post after the first paragraph. Some will use Avgas simply for the octane rating, having no inkling what it really means. Or simply for the smell. All that corrosive talk and damage, that's for some other guy. Or their grandpa reminiscing about the good ole days of leaded car gas. The idea that their bike actually runs better on pump gas just can't be. I mean it's 100 octane with lead... right? That's better than 90..right? Your bike was designed to run on readily available pump gas.

The only bike's that I've ever owned that pinged(I've owned dozens) were the 1981 yz465, 1982 cr480 and the 1981 Maico 490. The yz needed some jetting and a little race gas 50/50. The cr ran forever, pinging all the way. The Maico blew up regularly. Every other bike ran just fine on premium unleaded pump gas.

BTW- I am a pilot and Airframe & Powerplant Mechanic ( A&P ).
WhatchaWant 9/19/2019 6:34pm
9/19/2019 6:34pm Edited Date/Time 9/19/2019 6:53pm
tek14 wrote:
About Avgas: AvGas is short for Aviation Gasoline. AvGas is of interest to motoring enthusiasts because of its availability, octane rating and low price compared to...
About Avgas:

AvGas is short for Aviation Gasoline. AvGas is of interest to motoring enthusiasts because of its availability, octane rating and low price compared to commercial race fuels. AvGas might seem an obvious choice but closer study raises some doubt.

AvGas LL100 stands for "Low Lead 100 Octane". TEL (Tetra-ethyl-lead) is added to raise the octane. When used in a motor vehicle this fuel will leave a lot of lead deposits in the motor. 100LL has a high lead content (0.5 grams per litre), even higher than leaded race fuels. The deposits left when TEL(lead) is burned are corrosive and damaging to valves, valve guides, valve seats and cylinder heads. Lead deposits will also block oxygen(lambda) sensors and catalytic converters and foul spark plugs even after only a short use. Also, 100LL has a chemical package added to make it perform at high altitude, and that isn't the best thing for motor vehicle performance here on the ground.

AvGas is blended for large-bore, long-stroke, low RPM engines which run at high altitude. While AvGas' higher octane is useful, smaller-bore, shorter-stroke, high RPM engines will perform better on racing fuel or high quality octane boosters. AvGas has lower volatility so when used in proportions higher than about 40%, part-throttle drivability and cold starts may be compromised. AvGas has a lower specific gravity so it will require a change in air-fuel ratio calibration for the engine to perform at its best. LL100 is blended with a high percentage of aromatics causing reduced throttle response which is not an issue with an aircraft engine but certainly an issue in a high-performance automotive engine. These high levels of aromatics will also damage rubber components in automotive fuel systems such as fuel lines, fuel pump seals and injector washers.

TexasVet wrote:
While trying to be as respectful as possible(to the folks who quit reading it), a lot of folks quit reading your post after the first paragraph...
While trying to be as respectful as possible(to the folks who quit reading it), a lot of folks quit reading your post after the first paragraph. Some will use Avgas simply for the octane rating, having no inkling what it really means. Or simply for the smell. All that corrosive talk and damage, that's for some other guy. Or their grandpa reminiscing about the good ole days of leaded car gas. The idea that their bike actually runs better on pump gas just can't be. I mean it's 100 octane with lead... right? That's better than 90..right? Your bike was designed to run on readily available pump gas.

The only bike's that I've ever owned that pinged(I've owned dozens) were the 1981 yz465, 1982 cr480 and the 1981 Maico 490. The yz needed some jetting and a little race gas 50/50. The cr ran forever, pinging all the way. The Maico blew up regularly. Every other bike ran just fine on premium unleaded pump gas.

BTW- I am a pilot and Airframe & Powerplant Mechanic ( A&P ).
Well, 99% of his article is flat false.

If they were true, according to the article planes wouldn't start in the cold, and high performance engines would have problems, so that means air race planes would be falling out if the sky.

And it's pretty well known aromatics don't cause rubber problems but alcohol does, which av gas has zero.

Also, where it states there is a chemical package for high altitude, I would love to see that on any brand of Avgas SDS.

Because, well, they are available to anyone and there are no special chemicals.
It is nothing more than a 100 Octane race fuel when you compare SDS sheets showing the ingredients.

In fact, my airport has SDS's available right at the pumps for anyone.

I'm having good luck with UL94 and soon UL102 Avgas will be available.
Probably be more $$ though since TEL is cheap.
TeamGreen
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TeamGreen 9/19/2019 6:40pm
9/19/2019 6:40pm
tek14 wrote:
About Avgas: AvGas is short for Aviation Gasoline. AvGas is of interest to motoring enthusiasts because of its availability, octane rating and low price compared to...
About Avgas:

AvGas is short for Aviation Gasoline. AvGas is of interest to motoring enthusiasts because of its availability, octane rating and low price compared to commercial race fuels. AvGas might seem an obvious choice but closer study raises some doubt.

AvGas LL100 stands for "Low Lead 100 Octane". TEL (Tetra-ethyl-lead) is added to raise the octane. When used in a motor vehicle this fuel will leave a lot of lead deposits in the motor. 100LL has a high lead content (0.5 grams per litre), even higher than leaded race fuels. The deposits left when TEL(lead) is burned are corrosive and damaging to valves, valve guides, valve seats and cylinder heads. Lead deposits will also block oxygen(lambda) sensors and catalytic converters and foul spark plugs even after only a short use. Also, 100LL has a chemical package added to make it perform at high altitude, and that isn't the best thing for motor vehicle performance here on the ground.

AvGas is blended for large-bore, long-stroke, low RPM engines which run at high altitude. While AvGas' higher octane is useful, smaller-bore, shorter-stroke, high RPM engines will perform better on racing fuel or high quality octane boosters. AvGas has lower volatility so when used in proportions higher than about 40%, part-throttle drivability and cold starts may be compromised. AvGas has a lower specific gravity so it will require a change in air-fuel ratio calibration for the engine to perform at its best. LL100 is blended with a high percentage of aromatics causing reduced throttle response which is not an issue with an aircraft engine but certainly an issue in a high-performance automotive engine. These high levels of aromatics will also damage rubber components in automotive fuel systems such as fuel lines, fuel pump seals and injector washers.

TexasVet wrote:
While trying to be as respectful as possible(to the folks who quit reading it), a lot of folks quit reading your post after the first paragraph...
While trying to be as respectful as possible(to the folks who quit reading it), a lot of folks quit reading your post after the first paragraph. Some will use Avgas simply for the octane rating, having no inkling what it really means. Or simply for the smell. All that corrosive talk and damage, that's for some other guy. Or their grandpa reminiscing about the good ole days of leaded car gas. The idea that their bike actually runs better on pump gas just can't be. I mean it's 100 octane with lead... right? That's better than 90..right? Your bike was designed to run on readily available pump gas.

The only bike's that I've ever owned that pinged(I've owned dozens) were the 1981 yz465, 1982 cr480 and the 1981 Maico 490. The yz needed some jetting and a little race gas 50/50. The cr ran forever, pinging all the way. The Maico blew up regularly. Every other bike ran just fine on premium unleaded pump gas.

BTW- I am a pilot and Airframe & Powerplant Mechanic ( A&P ).
Wait a tic...

You left a lot out:
1. The Maico was gonna blow up anyway Laughing
2. The Honda "sorta pinged". It was the '84 500 that REALLY pinged!
3. I thought that Yamaha simply needed "resquishing"?

Great post, well...
Except that part at the end where you admit to not working very hard (Yes, I'm an aviation smart ass, myself).

Pit Row

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YamahaJT1
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YamahaJT1 9/20/2019 4:02am
9/20/2019 4:02am
dcg141 wrote:
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead...
AV gas until this year still was still leaded. I had a customer with some build up on his power valves that looked like the lead deposits from spark plugs when cars still used leaded fuel. I have never seen that before. It was starting to clog the expansion chamber where it fits into the cylinder. I asked him if he was using pump fuel and he said no but would not tell me what he was using. I was wonder if anyone using AV gas in 2 stokes have even seen power valve issues.
YamahaJT1 wrote:
100LL now contains no TEL? Please share how you determined this.
WhatchaWant wrote:
For the last year I've been running 94 UL Avgas and to date have burned about 200 gallons with 60 gallons just over Labor day. It...
For the last year I've been running 94 UL Avgas and to date have burned about 200 gallons with 60 gallons just over Labor day.
It cannot be used in all airplanes unless spec'ed by the OEM for use so airports with it still sell 100LL.

It is basically 100LL without the lead. It's not available everywhere but my race engines require 93 Min but the OEM preferred fuel is 100LL.

They run at 8-9K for extended times. Plus it smells yummy and costs 4.25-4.50.


I was referring specifically to 100LL, but...

Yes, I am aware of the UL94 and UL102 offered by Swift Fuels: https://swiftfuels.com/fuel/unleaded-ul94-avgas/

I run 2-strokes, so the 100LL @ 50/50 with E0 90-93 with Maxima K2 @ 32:1 is nice for my CR125s.

There is an airport within 20 miles that has the UL94. Based on approximation with it having a MON of 94, it has roughly a (R+M/2) of around 98 octane.

I am gonna burn up my last few gallons of 100LL and give the UL94 a go to see what transpires.
RCF
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RCF 9/20/2019 9:03am
9/20/2019 9:03am
TexasVet wrote:
While trying to be as respectful as possible(to the folks who quit reading it), a lot of folks quit reading your post after the first paragraph...
While trying to be as respectful as possible(to the folks who quit reading it), a lot of folks quit reading your post after the first paragraph. Some will use Avgas simply for the octane rating, having no inkling what it really means. Or simply for the smell. All that corrosive talk and damage, that's for some other guy. Or their grandpa reminiscing about the good ole days of leaded car gas. The idea that their bike actually runs better on pump gas just can't be. I mean it's 100 octane with lead... right? That's better than 90..right? Your bike was designed to run on readily available pump gas.

The only bike's that I've ever owned that pinged(I've owned dozens) were the 1981 yz465, 1982 cr480 and the 1981 Maico 490. The yz needed some jetting and a little race gas 50/50. The cr ran forever, pinging all the way. The Maico blew up regularly. Every other bike ran just fine on premium unleaded pump gas.

BTW- I am a pilot and Airframe & Powerplant Mechanic ( A&P ).
I had a guy bring KTM RFS told me he couldn't start the thing , I said I'd check it out I open the gas tank and smell that I had to race fuel in it dump that out and went to the gas station bought some regular gas and filled it up. the the bike would start one kick every time those first KTM four strokes were made to run on low octane gas it said it right in the manual but some people think they need high octane fuel for everything.

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