Is anyone running no lead race gas? What are your thoughts? Anyone dyno tune with race fuel and without?

high compression and air cooled dont work well

Wondering if a tuner can squeeze out more power. that and I need it until i get a tuner.

 

It would be good if you told us what motor you have and how it's been modded. If it's stock race gas will not help. I assume since you don't have a tuner that it's stock, and if you want more power you at least need to start with a stage one setup.

 

What’s better than race fuel? Airplane fuel. Out regional airport sells it to the public and it’s a whole lot cheaper than VP.

 

If your engine is not pinging on regular gasoline why would you want to use higher octane? There's no more energy in high octane than there is in low octane.

 

"Race Gas" won't give you more power, although some high-power builds will require it. When you see someone running racing fuel and making lots of power, it's the engine specs that are making the power, not the fuel. There are lots of other variables but simplistically, very high compression can require high octane, and so can lots of spark advance. If you have the ability to change advance easily (based on what fuel is in your tank), then you may end up with a few more horses.

 

Let me clarify.

2011 FXDC 96" motor (stock) w/ slipons which are practically straight through. Stage one air cleaner. NO fuel management.

Motor detonates (very audabily) under load. Im ok spinning 1st and 2nd but the top of 3rd, all of 4th under load. 2 up and sound like im crushing rocks.

Understand in TX we have HOT and humid weather.

Air cooled engines down here are a PITA. I had VW motors ping on 93 octane w/ 9-1 comp ratio with mildly bumped timing. and reducing timing creates more heat not less.

Also, I do understand the concept of stoichiometric AFR ideally and the fact AFR is governed by intake volume, IAT, O2 , timing, fuel, etc

At this point in time. 3 gallons of VP isnt going to break the bank until I can get a tune


ALSO, AV gas tears up O2 sensors.. no AV in the bike

 

Octane, and/or race gas, does not add power. I only helps to enable higher compression and aggressive spark advance whilst preventing pre-ignition.

 

exactly, i have all 3 for my riding conditions. I cant turn a dist to pull timing, i cant screw in a new jet, and i cant shim a jug.


SSSSOOOOO, whats left a tuner or octane

 

Nu-Tech fuel can get you some add'l torque, compared to regular street fuel. But, it's very expensive.

If you're "pinging," you need to get the contributing factors reduced to the point of no more pinging. You know what factors that need to be modded. You've listed them above.

Getting your cylinder head temperature under control is also a huge factor. (I know, I know, God said, "Let them remain air cooled...")

Unfortunately, the one liquid cooled engine that HD made was not widely accepted. The current renditions of that engine are falling on deaf ears as well.

 

Your symptoms could point to excessive carbon buildup in the combustion chamber. That's what caused me to tear into my motor a couple of years ago. Carbon buildup reduces combustion chamber volume, which raises compression. And it's definitely worse when hot, and more prone to happen in high heat.