I'm doing about the same thing Streetrunner is doing on my 07 Ultra with stage one AC, PCIII, and Rinehart's . That is down from my factory numbers originally but its alot more than my truck or car get and I have more fundriving it too.

 

I get between 38.5 and 40.5 MPG on my '08 Ultra with a 103"Stage IIsetup, SEAC, SERT and SE street legal/street performance mufflers. I have over 4000 miles on the bike but only about 1500 on the build.

 

Around 43 mpg on my girl... "D"

 

My 08 UC was got 33-35 MPG for the first 1000 mi or so.
Approching 5000 mi now and get about 40-42 MPG.
Most miles are on 2 lane flat highways 55-65 MPH and run 92-93 Octane fuel.

Inmy pick-upIhave noticed that mileage is2-3 MPG worse with gas I get in northcentralIllinois than it is when I amout of state also loose a couple MPG during winter.

 

Mid 30s on the '08 RKC until I hit 1200-1500 miles, then it jumped to low to mid 40s. The wife's '08 Deluxe was upper 30's until around 1000 miles, then it shot up as well to the mid 40's. We ride in a lot of mixed traffic.

 

What map are you running? I have a similar setup except with Rush mufflers and K&N AC. My mileage varies, but in the conditions you describe I get about 50mpg. It drops as the speed increases and lingers around 40mpg in city riding, but is generally very good as long as I keep it warm, do little accelerating, and keep the speed moderate. You can improve your mileage by leaning the cruise range using your PC software, but it's a tricky proposition, as you don't want to overdo it. There's quite a bit of discussion on this topic if you'll do a search on "PCIII mileage", but I think the search function is down again.

 

I just did a run to Daytona and back last weekend. My low fuel light was on around 140-147 miles and I'd run it to about 160-165 and fill up usually with about 4.5 gallons. Looking at rough numbers I was getting 36-37 mpg which to me sucked.

I filled up in Daytona on Speedway Blvd and noticed the "May contain up to 10% ethanol" statement. I was watching the races so didn't do much riding. Just to the track and back to the Super 8 a couple of times. Then headed north. That tank of gas the low fuel light came on at 127 miles. My limit was 150 miles on that tank prior to filling up and I barely got to GA Exit 3 on I-95 and "Blues BBQ" where I gassed up and got a brisket sandwich.

Then off ethanol I was back to the 140s low fuel indicator.

All this was highway miles at 80+. With this bike I can't even get to the mileage (170-175) where the low fuel indicator used to come on with my '03 RK. Most miles on a tank I got out of that bike was 212 and still had a 1/2 gallon of gas left. I miss the range.

The RK was a 88 5-speedwith just a Stage 1 flash and this is the 103 Stage II with the 6-speed.

 

I got 35 with my 07 Heritage, picking up a 07 Ultra on Saturday, hope it's better.

 

06' w/a stage 1 and fatcat exaust,43-45 with 2-up and 70mph, got as low as 39mpg with mountain terrain and two up.

 

Mines better than that, I last put gas in mine in November, still got almost full tank. That's about 4 months to quart.

Actually, Stage I & PCIII set-up on a 96Evo Ultra, anywhere between 45-51. Almost 230 miles on atank beforered light come on.