octane question
Road Master
Joined: Apr 2009
Posts: 754
Likes: 24
From: Southern Maine
I run 93 most of the time but she runs fine on the 89 when I have to put it in. I keep a bottle of octane booster in my bag during the hotter part of summer just in case but I haven't needed it yet.
Cruiser
Joined: Feb 2010
Posts: 179
Likes: 0
I run premium in my bike no matter what. And if I am not mistakin the octane rating is a a required minimum. I think that if it says 91 then that is the least it can have and it could be more. So it could be 93 at the stations that have 91. Hey but I have been wrong before
Road Master
Joined: Feb 2011
Posts: 1,120
Likes: 4
I use 91-93......because the manual says 91 min. but I have a freind that races cars and he can't understand why the min octane is so high. The compression ration of the 96 cu in displacement engine is 9.2-1 which isn't really that high. Anyone know why HD requires 91 min.....is it for a longer burn?
Road Master
Joined: Apr 2009
Posts: 754
Likes: 24
From: Southern Maine
Must be nice to have all that 93 available 
, when a station up here has it, they fly a big banner to advertise it. I guess i got to get out of Maine more.
, when a station up here has it, they fly a big banner to advertise it. I guess i got to get out of Maine more.
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Cruiser
Joined: Sep 2010
Posts: 215
Likes: 1
From: Central Illinois
I run 93 ALWAYS, but I was just introduced to a new product KLOTZ octane booster it is a 1/1 mix (1 oz. per 1 gallon) it boosts octane 7-10 points, has a lubrication factor, and a odor additive (smells like you are running VP or Turbo Blue racing fuel)
Tourer
Joined: Oct 2009
Posts: 325
Likes: 1
From: missouri
I usually go middle of the road and fill with 91 octane. I used to have a dual purpose bike and I remember the manual warning against using high ethanol fuels. I can't remember why, and I'm at work and do not have my harley manual here, but are there similar precautions these days about high ethanol fuel in bikes?