Which do you use?
I have a new 883 superlow. My son says I should use 93 octane.

 

My manual calls for 91. We don't have 91 around here so I use 93 and it runs great.

 

The H-D owners manual does not call for 91 it recommends it. There is a world of difference between a requirement and a recommendation.

Why don't they require 91 or higher? Because our nanny government dictates that any vehicle sold for highway use in the US MUST be able to run on 87. That is part of the job that the ECM and nine sensors to take care of.

I have many posts over the years about how I run 87 in 883's, 1200's, TC88's,TC96's, TC103's, TC103HO's, TC110's and TC120's with getting more power, mpg and cooler running.

Collectively I run them 30 to 40K + per year. No pinging no issues. I have over 10K on one TC120 with 87 octane from day one.

It is a process of setting the AFR, iridium plugs, oil cooler, tank lift (cooler heads) high flow intake and stock exhaust that facilitates using E1087 octane.

Octane is not power it is the measurement of a fuels resistance to ignition and burn rate. The higher the number the harder to ignite so less burns during the combustion cycle. The less burned the less BTU's produced the less power made and the more the engine is fouled.

However, if the compression has been raised over stock, the spark advanced as it is from a stage I tune on and the higher performance cams added higher octane becomes a must.

I have been messing with high performance engines for 60 years from muscle cars to Vettes and Vipers. Now I focus on getting the most mpg out of a V twin H-D engine. I have done 25 since 06 with 21 still in the garage. My latest effort is a new Roadster.

 

I use 91, that's the highest I can get around here

 

here in the Peoples Republic of CA we have really crummy gas- even though a lot of it comes from here- I use the highest octane available in my bikes... premium !

 

Thanks, I think I will run a couple of tanks with 93 and see what kind of MPG I get.

 

Premium for my stage 1 883. I ran a tank of 87 last year, and it ran like crap; hesitating, knocking, etc...

Last weekend I got 55mpg while cruising around Washington.

 

All I heard was "Don't buy any of my bikes at the auction".

 

My basically stock (larger jets and opened AC) XL1200R does not run well on 87 octane, wish it did. The manual calls for 91, so that is what I use when I can get it - higher if I can't. Most around here have 92 or 93, very few with 91.

 

I run 93 here from only one station, it is the only non E10-E85 gas in our area, Ethanol is not good for your engine.