Mileage stinks!
Seasoned HDF Member
Joined: Dec 2007
Posts: 8,341
Likes: 714
you might get 50 if your bike runs even leaner than most and your speedo is off by more then most.if you put a couple different harleys(same year and model)you won't believe the differences in the mapping,its tolerance build up,between all the hardware and software there is a lot of stuff that can be off by a little and it adds up to a lot.
Seasoned HDF Member
Joined: Apr 2012
Posts: 9,980
Likes: 5,218
From: Michigan
It's important that we compare apples-to-apples, and not apples -to-oranges.
The larger bikes (Ultra's, Limited's) weigh more than RK's, SG's, etc., so it makes sense that they will use more fuel.
Other factors include upper and lower fairings, windshield height, and tour packs.
Another thing to consider is the size difference between the T/C 88, T/C 96, T/C 103, and the S/E T/C 110.
I have a '13 CVO S/E Ultra with Rinehart XT True Duals with a SERT and a dyno tune.
My riding partner has a '10 Ultra that has been upgraded from a 96" to a 103" and he as V&H Monster Ovals with a SERT and also a dyno tune.
Running together, my bike always uses more fuel than his, but in a 200 mile run, I think the largest difference in fuel consumption was once 0.4 of a gallon, but most times it's usually 0.2 of a gallon.
Running at 70 MPH, we usually get 40 +/- MPG, and running between 75-80 MPH our mileage drops to about 38 +/- MPG.
The RK's will usually run in the mid 40's MPG, and I've had two stock Heritages ('92 and a '95) that would get 50+ running at 70 MPH, but one you (we) start tinkering with the A/C, pipes, larger jets and race tuners the MPG's start to drop quickly.
The larger bikes (Ultra's, Limited's) weigh more than RK's, SG's, etc., so it makes sense that they will use more fuel.
Other factors include upper and lower fairings, windshield height, and tour packs.
Another thing to consider is the size difference between the T/C 88, T/C 96, T/C 103, and the S/E T/C 110.
I have a '13 CVO S/E Ultra with Rinehart XT True Duals with a SERT and a dyno tune.
My riding partner has a '10 Ultra that has been upgraded from a 96" to a 103" and he as V&H Monster Ovals with a SERT and also a dyno tune.
Running together, my bike always uses more fuel than his, but in a 200 mile run, I think the largest difference in fuel consumption was once 0.4 of a gallon, but most times it's usually 0.2 of a gallon.
Running at 70 MPH, we usually get 40 +/- MPG, and running between 75-80 MPH our mileage drops to about 38 +/- MPG.
The RK's will usually run in the mid 40's MPG, and I've had two stock Heritages ('92 and a '95) that would get 50+ running at 70 MPH, but one you (we) start tinkering with the A/C, pipes, larger jets and race tuners the MPG's start to drop quickly.
Elite HDF Member
Joined: Oct 2010
Posts: 3,504
Likes: 12
From: DOWN SOUTH
Let me get this right, you do all that go fast stuff which basically means you are forcing more air and fuel through the motor to make more and more power but still expect super MPG?? Anyone who has all that and still is claiming 50 MPG I would have to say BS. The mileage you are getting is pretty normal for all that you did to it. If you expected to gain MPG which is usually around 42 MPG stock by feeding more fuel and air, you must have been dreamin.
LOL, you NAILED IT!!! Do that much to an engine MPG is going WAY down.
Road Captain
Joined: Nov 2012
Posts: 649
Likes: 22
From: Lakeland FL
yeah I have a real hard time believing all these claims of 45-50 MPG I can tell you my last 3 Harleys have been a 07 Dyna 96" a 13 RGU 103 and my new 14 Limited 103 and they all have gotten right around 36mpg the Dyna being a smaller bike got a best of 38mpg but it did have a stage 1 air cleaner and SERT installed.
Road Master
Joined: Mar 2013
Posts: 1,151
Likes: 14
From: Seattle
As your speed increases, so does the wind resistance on your fairings and windshield. In my experience if I'm going 60 or less (in 4th or 5th)on back country roads, I get close to 50 mpg. Higher speeds or around town I'm averaging just under 40 mpg. Stock everything at this point.
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Road Captain
Joined: Apr 2011
Posts: 702
Likes: 1
From: Kawartha lakes, Ontario, Canada
2012 FLHTCU. 103. Rush racing true dual exhaust, SERT, K&N breather with the stock football cover, dyno'd and runs good...the a/f ratio is perfect, running just where it should, putting out 105 ft/lbs torque and 98hp...
And my mileage will run 33-37 mpg no mater how easy I run it solo or getting on it 2up with bags.
I see some of you guys getting as much as 50mpg. Am I the only one seeing this low of mpg????
And my mileage will run 33-37 mpg no mater how easy I run it solo or getting on it 2up with bags.
I see some of you guys getting as much as 50mpg. Am I the only one seeing this low of mpg????
Last edited by jazzy jack; Oct 5, 2013 at 01:02 AM.
