Jump to content

AVGAS VS. RACE GAS?


donkeypuncher

Recommended Posts

  • Replies 38
  • Created
  • Last Reply

Top Posters In This Topic

To answer your question first, I'd say that if cost was of no concern, of course I'd want to run Race Gas.

 

That's what these small manufacturers make. Specialized Race Fuel. It should be as good as can be. Of course, one of the things that differentiate these race fuels from standard pump fuels is the lack of emissions related additives and the very close consistency from one batch to the next. That is what true racers need and are paying for. Consistency.

 

But in the real world, I've been running a 50/50 mix of 100LL AVGAS/pump premium for more than a decade in 2-strokes because it costs less than half the price of race fuels. All I can offer is what I've found so far....

 

I took the top end apart on my 2000 YZ250 to replace the piston/rings after 4 years of mega riding. Piston dome was clean and carbon free, as were the ring lands, and transfer ports. I literally wiped away the discoloration. I use Yamalube 2R at 32/1.

 

I just looked through the exhaust ports of my Banshee while I had the pipes off and plugs out. I could read the part #'s on top of the pistons (100% carbon free) and the exhaust port/domes are spotless too!!

 

2-strokes operate best on leaded fuel. Period. Longevity is increased because of the lead lubrication. I've been running the same plugs going on my 3rd season so I don't understand why some claim to have carbon/fouling issues...it certainly isn't because of the fuel!!

 

100LL is an ultra clean fuel. One of the specs is that they place an amount on a stainless steel tray and it can't leave any deposits behind. Another spec is that it has a 15 month shelf life...compare that with standard /race gas of 5 weeks.

 

In it's liquid state, it doesn't smell like fuel as we are accustomed to, but it works great for me. If it atomizes well enough in a thin air environment (10,000') it will do an outstanding job at sea level too.

 

I did an internet search on the properties of 100LL and I'm satisfied in it's ability to kick every 4-pokes ass up Old's :cool: without detonation.

 

BTW: Someone commented on the outboard application with 100LL. The TCW oil used in outboards is some vile stuff.

NEVER run that crap in your Banshee!!! It's for use with cold water intake...not a hot water recycling radiator cooling system. Plus, who can attest to the condition of said motor? "You know, my friend's friend's friend's brother said his uncles motor...."

If the low RPM thing people throw around about AVGAS had validity, it would operate better in outboards because of their (approx) 5500RPM redline.

 

My $.02.

 

I used to run F&L 111 leaded Race gas in my banshee, the plugs would foul up with lead all the time and would need to be replaced often. Soco now sells unleaded VP110, I no longer have lead caking on my plugs. It used to look like a greenish substance, but thats probably because I was mixing with MC1 back then. I have never tried AV gas. I don't know why some bikes have the issue and others do not. My Friend ran the same fuel and never had any problems and even ran the same plugs.

Edited by Justintoxicated
Link to comment
Share on other sites

I used to run F&L 111 leaded Race gas in my banshee, the plugs would foul up with lead all the time and would need to be replaced often. Soco now sells unleaded VP110, I no longer have lead caking on my plugs. It used to look like a greenish substance, but thats probably because I was mixing with MC1 back then. I have never tried AV gas. I don't know why some bikes have the issue and others do not. My Friend ran the same fuel and never had any problems and even ran the same plugs.

 

 

not to burst your bubble but vp 110 is a leaded fuel. :shrug: fuel can only get high motor octane numbers by adding lead to it.

 

the only thing i can think of is f&l 111 has a higher lead content the vp110.

Link to comment
Share on other sites

Now isnt Av gas 130 octane??? Even tho its CALLED 100ll, its actualy 130.

 

http://www.aviationfuel.org/avgas/avgas_specs.asp

 

Look there, Under rich conditions 130 octane, Now isnt that pushing the octane level of alky?

 

I have always had to go to massive jets to get my bikes cooled down properly on av. About half of what i have to go to on alky. I also dont get pinging on the 240psi 250r engine on av gas.

Link to comment
Share on other sites

Now isnt Av gas 130 octane??? Even tho its CALLED 100ll, its actualy 130.

 

http://www.aviationfuel.org/avgas/avgas_specs.asp

 

Look there, Under rich conditions 130 octane, Now isnt that pushing the octane level of alky?

 

I have always had to go to massive jets to get my bikes cooled down properly on av. About half of what i have to go to on alky. I also dont get pinging on the 240psi 250r engine on av gas.

 

how they come up with 100 octane is by testing the fuel, the aviation lean test, this test is like the mon (motor octane number). mon is the octane number you need to look for when using race fuel. it is a test that is the closest to the conditions that go on in your engine. so when looking at the octane numbers this is the MOST IMPORTANT NUMBER. the 130 octane is the aviation rich test, this test is determend by simulating a supercharged condition, elevated temperatures, and a high manifold pressure.

 

if you look under http://www.aviationfuel.org/avgas/grades.asp thats is the same website you posted but it talks about the grades.

 

stated by them "Avgas 100/130 can be used in some automotive engines. It has both research and motor octane numbers slightly over 100." i don't know what they consider slightly, is that like 100.5, 101, or 110. slightly could mean different things for different ppl.

 

its called 100ll because thats what it probably is. i have friends that build the business class interiors for emirates and they tell me how anal they are and that they have strict rules about what can be done to the airplane. so i would think that there are strict guidelines when it comes to the fuel. imo.

 

That's not even kind of true.........

 

There are many other octane increasing agents (most of them are some sort of synthetic substance) out there besides lead.

 

what i should of said is, lead increase the octane number in fuel. sorry about that my mistake. :down::banghead:

Link to comment
Share on other sites

what i should of said is, lead increase the octane number in fuel. sorry about that my mistake. :down::banghead:

No problem......... :beer:

 

Another interesting thing about lead in gasoline is that it's also a lubricant. Unleaded fuel has elements to replace it (sulfur, etc.), but they don't quite behave the same.........

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...