This might be awhile.......

 

LOL, Shovelhead riders said the same thing about your evo and, Panhead riders said the same thing about Shovelhead riders...LOL

 

OP In am in North Dakota too and I run mostly 91 because in a lot of stations its the only non ethanol grade available. The state of ND subsidizes the cost of ethanol here so most gas stations have it in the tanks.

Just stay away from ethanol blends and you will be fine.

 

Came across a guy using blendzall #485 octane booster in his bike the other day. smells good too.

 

I use E0, & around it it is all 91 octane. Plenty of places to get E0 around here, since Florida is a boating state.

 

The higher octane has nothing to do with "quality." As said before, it has everything to do with how much the fuel can be squeezed before it detonates. HD doesn't recommend higher octane fuel because of high compression ratios, it recommends higher octane fuel because of the heat our engines see. As heat goes up, the likelihood of detonation (or premature ejac... ummm ignition) also goes up. That being said, a modern bike has a knock sensor that monitors for detonation and adjusts the timing curve to minimize it. Don't sweat it so much.

 

Except for the first 6 months, I've been using regular since I've had my bike.

 

I use what the owners manual says to. That said I use 87 in everything but this bike. Every once in awhile I put in 87 out of habit. It was no problem at all.

 

We have both 93 & 94, both with ethanol. The 91 only used to be E free, but not any more. I use the 93/94, figure it costs me maybe $2 a tank, so what

 

Twin Cams are designed to run on gasoline with an ethanol content of "up to" 10% (E10)... so E85 is a BIG NO NO!