My twin cam ran fine in Colorado & yes the octane ratings were odd, 85, 87, 90 but no issues. Had some 104+ octane boost in case I could only find 85 as there was a gas shortage around there in '21. I did have a severe lack of power on my Intruder 1500LC which has a carburetor on another trip. Ran well enough but not much power.

 

I am sure it has gotten better, but my 07 has it, and I would hate to see how bad it is without, cause it ain't that good with

I have never heard of running lower octane, when I have been out, I think 87 was lowest. Some places in canada had higher octane than what I was used to seeing out west which is 91 sometimes 93. Some places in canadian rockies I used boost even for my 07. Though I don't think the 07s had the best mapping and were known to have pinging issues. I never had awful problem as long as I kept rpms up.

I just gogoled this and they said you can get away with 85, but if pings go higher, this was a car website. Cars normally run low octane. Only palce around here to get 85 octane is flexfuel. I trust my cars FI, more than my bike.

I am curious, never seen 85, but have not been in mountains for 10 years.

Octane threads usualy are hottly debated, and eventually break down. I am curious to learn, my experience was to run high octane. But I also caution a harley is not a car or jap bike.


I ran it in canadian rockies at time, but not in US, atleast the areas I rode.

 

Not a lot of meat in this article, but it talks about colorado running 85. Claims runs better. I question the state of colorado politcs, why are other states not running it. And a car is not a harley. I have a lot more faith in my trucks FI, which I always run 87.
https://www.cpr.org/2022/01/04/color...2Doctane%20gas.
I have also read on breif google, not all the 85/87 is ethanol,but pure gas. That is not the case everywhere. To the east, you have to buy premoum to get non ethanol. Then you get into the debate about ethanol and when it denotates.


I suspect hottly debated, you find it disucssed on car sites
From Ford, which I am sure has a lot better FI then we do.
“Your vehicle operates on regular unleaded gasoline with a minimum pump (R+M)/2 octane rating of 87. Some fuel stations, particularly those in high altitude areas, offer fuels posted as regular unleaded gasoline with an octane rating below 87. The use of these fuels could result in engine damage that will not be covered by the vehicle warranty.
https://pickuptrucktalk.com/2022/04/...atings-matter/
Article also discusses other manufacturers, which vary on what to do.

 

Well Scooter, he had a technical question and searched the forum for an answer. He did the proper thing and continued an old thread that was the same topic.

 

Why invent the wheel, especially on technical discussion that has info? Some people just want to bully people, even if it makes for a worse discussion.