TC88 mpg?
Elite HDF Member
Joined: Jan 2007
Posts: 4,020
Likes: 69
From: Twin Cities, MN
I have a very similar set up, except the carb and stock head pipe. But I get 38-42 mpg on a regular basis. Wish I had an answer for you.
Road Master
Joined: Jan 2014
Posts: 1,036
Likes: 25
From: Texas
ive got the SE Stage 1, Hooker Tuned Flow slip-ons, and an unknown tune, and pending how i ride, i average around 37mpg. i discovered if i do a lot of engine-braking to slow down, my gas mileage can drop fast. bout 2 weeks ago after a particularly agressive weekend, i got only 22mpg. the next tank was 36. i need to have this bike re-tuned at some point in the near future.
This post title reads, TC88 MPG, my old LowRider with Stage I and a Power Commander
III USB download got 45 to 48 MPG on the highway in town 40 to 42, it was a 04 TC 88.
The last tank on the 2014 Rushmore 103 High Output, all stock, was 41.3 MPH, with some
town and mostly highway.
III USB download got 45 to 48 MPG on the highway in town 40 to 42, it was a 04 TC 88.
The last tank on the 2014 Rushmore 103 High Output, all stock, was 41.3 MPH, with some
town and mostly highway.
Outstanding HDF Member
Joined: Dec 2007
Posts: 2,403
Likes: 20
From: Indy
I normally get in the mid to upper 30s, and on a trip to Florida last summer got 41 or so, but I hardly ever get that much.
I don't check it too often, but I think if you do every so often, you can tell if something isn't right.
I don't check it too often, but I think if you do every so often, you can tell if something isn't right.
Road Captain
Joined: Apr 2011
Posts: 687
Likes: 58
From: Frederick Co, MD
I get right at 38mpg, all the time - city, traffic, twisties, slab. My PCIIIusb just went **** up, so I'm replacing with a PCV. I might spring for an auto tune too if it really can increase mpg while also making the bike run better.
Tourer
Joined: Jan 2012
Posts: 419
Likes: 60
From: Central IL
I have a very similar setup to yours-TC88 with 21 cams and I get around 40 or a little better. I think your low mpg is an indication of a poor tune. If it was tuned on a dyno then I'd take it back and have it retuned. You're probably running rich and there is likely more performance and mpg to be gained.
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Road Warrior
Joined: Aug 2006
Posts: 1,575
Likes: 7
From: Wisconsin
Until you get it on a dyno, you're going to be guessing at a map, but you are probably a little rich in the part throttle / cruise RPM.
FYI - My TC88 with S&S510C got 37 mpg with the cruise set at 65 -70 mph. If I went over 70 mph my gas milage got bad quick. I think I would get 31-33 mpg at 75 mph. When I did the big bore (to 95") it didn't seem to affect the gas milage much. Both the 88 and 95 versions were dyno tuned using a PCIII.
Good luck.
FYI - My TC88 with S&S510C got 37 mpg with the cruise set at 65 -70 mph. If I went over 70 mph my gas milage got bad quick. I think I would get 31-33 mpg at 75 mph. When I did the big bore (to 95") it didn't seem to affect the gas milage much. Both the 88 and 95 versions were dyno tuned using a PCIII.
Good luck.