I was having a chat with my Indy the other day and he said he tells the guys with the HOT motors to spike there fuel with C12 or C16 race fuel.

I cant remember what he tells them to mix in, it cant be much, with my 4.9 gal. Dyna i was thinking maybe a quart at the most.

Just wondering if anybody else dose this. and how much do you mix??

I filled up a while back with straight 100 oct. and my bike ran like ***.

i believe that the higher octane required a leaner AF ratio, so i diluted it with 91 as quick as i could and the bike drivablity returned shortly after.

 

I run good BP 92 octane fuel in my Harley's, and even here in the lower Midwest where temperatures can reach extremes (well over 100 degrees in the summer).

Don't even have a problem running 'un-spiked' 92 octane fuel in my built 95" 2003 WideGlide, which is running a Mikuni HSR 42, JE 10.25 forged pistons, high lift Screamin' Eagle 258 cams and modified heads.

I figure why spend additional money for fuel additives or mixing race fuel if it isn't needed.

 

I have in my Softail, I don't know how much of a difference it really made, but I did it. I started off using the octane boosters and then progressed to adding a gallon of 112 race fuel at about 1/2 gallon per every other tank (I never go below a quarter, so it would have diminishing levels). I gotta be honest, I don't know from a functional level how effective it was, my goal was increased performance not ping resolution. Basically it was purely a method to measure myself w/o use of a ruler... if you catch my drift. Dunno maybe it works, maybe not- I stick to high test 91-93 depending on the gas station and am still quite happy.

 

I totally agree, i wish i had better fuel out here in cali.

i have a friend in Arkansas, and he can have quite a bit more engine that i can out here with 91 oct.

 

I used to run my evo chopper at the drags and find that adding an octaine booster lets a hog put out a little more power. With the long strokes you make use of that slower burn. I don't think there is much difference on the street where most of your time is spent cruizing not running ***** out. I always run 93 over 89 or 91 for the same reason.

 

About every third tank I add a few onces of octane boost to keep things running smoother. Here in California the best we can get at the pump is 91 and even though I only buy Shell or Cheveron fuel its not consistent quality.

Good thread by the way.

 

I run just under 11-1 on my 93" shovel , while she will run on pump 91 you can tell in the starting and ping knock she does not like it . I'll mix 112 race fuel 1 to 4 when I can and she perks up very nicely . Straight 98 is the **** but @ $6+ a gal ...................................

 

In my 2010 Heritage owners manual it says:

" Do not use race gas or octane boosters. Use of these fuels will damage the fuel system."


...for whatever its worth....

 

Those newer bikes are so delicate

 

Im always surprised when i read about how low the octane rate is in the states,over in the U.K and i think in the rest of europe its 95 or 97,so i assume the bikes must be tuned differently to take note of that, mind you we sure do pay for it around 8 to 9 bucks a gallon in your money.