100LL AvGas
100LL AvGas
Anyone running AvGas in their Harley? Was thinking about it today as I filled up and I was on my way to the airport. High Octane? Why not run 100LL AvGas in the Harley. Can't hurt it, can it? I used to run it in my 65' Impala Super Sport.
Grand HDF Member
Joined: Jan 2012
Posts: 4,456
Likes: 2,858
From: Oklahoma
Do you get a "deal" on avgas? In the lower 48 avgas is at least $1.50/gal. more expensive than mogas. Street engines only run at 65% and above power output in short spurts and "coast" most of the time. I suspect that there wouldn't be enough heat for the scavenging agents to keep lead deposits from forming on valves, plugs, and combustion chamber surfaces in addition to destroying the O2 sensors. Even if it were free it would be false economy with the increased maintenance expenses. With unleaded mogas being standard for over 30 years, I doubt that engine oils are formulated any more to hold lead from blow-by in suspension until drained. I also have no idea if lead will accumulate on the injectors and slowly clog them. All kinds on unknowns on this experiment.
Trending Topics
Cruiser
Joined: Jan 2005
Posts: 159
Likes: 1
From: Northern Manitoba, Canada
I use 100LL avgas in my 2-strokes and my 454 powered jet boat. 87 octane is all we can get here, so it is the only option for performance toys.
Avgas is less dense than auto gasoline, it needs 1-2 jet sizes bigger, usually. If you are EFI, you would have to re-map for it. It will kill cats and O2 sensors real fast. If you NEED that high an octane, chances are your motor will never have deposite problems, as you will be running it hard enough to burn them off.
Avgas is less dense than auto gasoline, it needs 1-2 jet sizes bigger, usually. If you are EFI, you would have to re-map for it. It will kill cats and O2 sensors real fast. If you NEED that high an octane, chances are your motor will never have deposite problems, as you will be running it hard enough to burn them off.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Outstanding HDF Member
Joined: Jun 2008
Posts: 2,132
Likes: 25
From: NorCal
A local 76 station has 100 octane Sunoco race gas.
After my buddy built his 124" Street Glide he thought it would be cool to run race gas.
We ran against each other afterward, me with my 96" Street Glide with Woods cams. We were neck and neck. He couldn't pass me.
I told him to switch back to 91 and let's run again. He spanked my bike hard.
Higher octane fuels burn more slowly and evenly. If your bike does not have the compression to support it the higher octane fuel is a waste of time and $$.
After my buddy built his 124" Street Glide he thought it would be cool to run race gas.
We ran against each other afterward, me with my 96" Street Glide with Woods cams. We were neck and neck. He couldn't pass me.
I told him to switch back to 91 and let's run again. He spanked my bike hard.
Higher octane fuels burn more slowly and evenly. If your bike does not have the compression to support it the higher octane fuel is a waste of time and $$.
Thread
Thread Starter
Forum
Replies
Last Post