153 Miles
Road Master
Joined: Sep 2007
Posts: 1,184
Likes: 0
From: The Peoples Republic of Massachusstts
My light goes on at about the same mileage interval 148-155 just depends. However when I fill at that point, I'm averaging 3.7 - 4 gallons, so I still have at least 1 gallon or so left. Puts me at the average of about 40 MPG. My best so far has been 223 miles to a tank, thats 44.6.
Now someone mentioned popping on slow downs, and I do get that once in awhile. I also burn 93 octane.
Most people believe higher octane burns quicker, it actually burns slower and longer than 87 octane. 87 octane fires very quickly and is good for multiple piston action, but in HDs you need the longer burning 91+ octane for a longer explosion inside the cylinder for push.
Now someone mentioned popping on slow downs, and I do get that once in awhile. I also burn 93 octane.
Most people believe higher octane burns quicker, it actually burns slower and longer than 87 octane. 87 octane fires very quickly and is good for multiple piston action, but in HDs you need the longer burning 91+ octane for a longer explosion inside the cylinder for push.
Seasoned HDF Member
Joined: Jan 2009
Posts: 5,142
Likes: 2,971
From: WACO
Yesterday my gas light came on at 163 miles and at 170 miles the neddle was on empty and as i was slowing down to come to a light and down shifted the bike started to turn off like it was completely out of gas so i went directly to the gas station and put in 4.9 gallons.
I just filled up my 07 Ultra. It got 34.491 mpg.
Stock. With ANBS A/C, Rush mufflers with 1-3/4 baffles, FuelMoto PC-V.
Average 38mpg without PC-V. 3rd map trying to get gas milage back. It was down to 30 mpg with 1st map. Very frustrating.
Cruiser
Joined: Jun 2008
Posts: 129
Likes: 0
From: South Dakota
Just came back from a 1000 mile run last weekend. Now here in my area the best gas I can get is 91% octane in a few locations. Mostly stuck with 87%. Mileage with running two up and at highway speeds I get around 36mpg. Now during this run I just came off of I was filling with 93%octane and running hard at 75 - 80mph between fill ups and averaging 42.8 mpg. Discovered that my gas in my area sucks!!!
Electra1
Electra1
Road Master
Joined: Jul 2006
Posts: 774
Likes: 60
From: here
A lot of the older Thundermax maps were programmed with an AFR of 13.0 across the board. Now that you found a shop that knows how to tune the Thundermax you should start to see better mileage....but if you ride hard on the acceleration your mileage will suck no matter what.
Supporter
Joined: Dec 2006
Posts: 6,723
Likes: 233
From: Altoona, Pa.
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Outstanding HDF Member
Joined: May 2009
Posts: 2,995
Likes: 1
From: South Florida
Guys i just don't know what else to try.I fill my bike all the way the rim with gas using 93 octane and my milaege goes to only 153 miles before the gas light comes on.
I'm getting 31 mpg is this ok and if not please tell me what can i check to make this milaege better.
I'm getting 31 mpg is this ok and if not please tell me what can i check to make this milaege better.
I've been know to get mid to upper 40's on my stock 2009 RKC. About 240 per tank.