Where I ride it has become very hard to find 87 Octane fuel that is NOT 10% ethanol. I have been using this fuel for about a year and averaging about 38 MPG. I recently found out that a local dealer has "straight" 87 octane gasoline so I started using it exclusively. Saturday went for a 280 mile ride with several folks(including Brother Bill) and we rode in the wind about 75% of the time. I averaged just under 42 MPG, stock exhaust, stock carburator and windshield.

I don't know that it was the ethanol but that is the only variable I changed.

Ethanol does not have the same BTUs that gasoline has. Look Here at a report on the subject.

Ethanol burns hotter and faster, so you will use more fuel.

Ethanol is not hotter than gasoline for a given volume. Ethanol's specific caloric output is more than 10 percent less than any non-oxygenated gasoline, so it takes more volume to produce more calories.

Science. see the link in the post by fireman922

I search out "real" gas also , but I only burn 91 octane "premium" in my 07 Roadie. I also use a octane booster by Lucas and my mileage out on the road will average 47 to 49 around town it will be around 40 to 42

The E-10 will lower your mileage. I hate the stuff. So does my bike.
I still feel like that's what caused my fuel sending unit to die at just over 38,000 miles. On a trip out west I had to use alot of it, because that's all there was. One of the contacts in the tank was eaten away. just my .03cents.

Here is a list states that do not and only sometimes require labeling. You may be using it and don't even know it. http://www.fueltestkit.com/state_guide_ethanol_laws.html

With 10% ethenol 89 octane fuel my bike got 42.5 mpg riding 2 up with a farily stiff headwind most of the time ,windscreen in highest most upper position for max protection from wind,went from stock 32T to 31T pulley for better gearing arround town and better pickup/perf which the small 1 tooth reduction helped but also increase cruise rpm a smidge (few hundred rpms),total of 4 fairly lrg 4 bags fully loaded,hitting quite a few hilly-mountain areas & running 70-72 mph @ approx 2,750-2,800 rpms the complete trip on the interstate per new tach i just installed and still got 42.5 mpg running ethenol fuel.

I get 44.5-45mpg riding 2 up in hilly/mountain areas at 50-60mph in mixed driving when cruising country roads closer to home.

My bike has road burner street pro's and stock but retians the stock lrg aricleaner assembly with as far as i know just a tweak to pms i did out to approx 3.25-3.5 turns to help a slight lean idle/off idle carb issue. I bought the bike used with pipes already installed so dont o know whic if anythng was done to the carb.

I asked the prior owner what if anything was done to carb jetting/pms/neeld clip adj and he didnt have a clue as to whjat iwas talking about,he said the dealer did the pipe install and anyhting that was required in that process was done then and he thought they did mention a word like jet kit so it may have been jetted but with 42.5 mpg they got it right which doesnt happen often,proper carb tuning is a ost art these days which i have been deal with woth almost 40 yrs working on classic muscle motors & being in the classic muscle car & classic jap motorcycle hobby too,have a 76 kawi kz900 and a 77 kawi kz1000 i bought new in 77 thats still on the road with only 27k miles on it that i also ride to this day .

I know you guys say just a pipe change doesnt normally require a jetting change but the roadburner pipes site states that for these particualr pips that are pretty darn loud with not much restriction from baffles need to be jetted and to me would seem to need a lttle fuel enrichment along the way other then just a pms tweak because the are muc less restricitve then the stock pipes.

But again i dont know for sure because lucky for me i have had no reason to chk the jetting because bike is running very well getting good mpg with std type & std heat range NGK's looking clean/good too.

Scott

Indiana does not require labeling, but almost all of the gas contains 10% ethenol. I didnt realize how hard real gas is to find until I started asking for it.

BlackHorse wrote:
Indiana does not require labeling, but almost all of the gas contains 10% ethenol. I didnt realize how hard real gas is to find until I started asking for it.
I live in IL and when i rode through IN, I noticed gas was .30 cheaper in IN. I wouldn't complain