Recently passed the 5K mile mark on my 08 Ultra. Was getting around 42-44 mpg (pre-5k), but am now averaging 47mpg on the highway (recent trip). I run HD synthetics and my mileage seems to be getting better with the break-in. I drive conservatively and am running stock pipes, etc.

 

Just got back from a 5000 mile trip, averaged 43.5, high of 50.1 and low of 36, this at high elevations, 89 and 90 octane fuel most of the time and 75+ mph. One run, 80+ for over 100 miles still got 44mpg.

Tuning is the key. 36mpg is too low for an engine with few mods unless you are continually whacking the throttle WFO.

For a carbed engine, you should be able to easily get it into the 40+ range. Have you done anything to the jetting or any other carb mods?

 

I consisentl et 43 -45 on my 08 RG with 12k miles thus far. Stage 1 with Fatcats.

 

I disagree that 36mpg is normal, much less acceptable, for highway riding. There isn't much you can do other than invest in an EFI controller, assuming you don't have a carburetor, as there isn't much you can do with the setup you have now. If you have a carb, buy a Thunderslide and install the jets recommended in the instructions, especially the low jet. I had one on my Evo RK and have installed them on a few TC's with great results. Mid-50's was routine on my old RK for highway riding, even in touring trim, and I wish I could get that consistently with my '07 SG. Only steady tweaking of my PCIII has allowed the bike to cross the 50-mpg barrier for conservative backroads riding.

 

I also have a carbed RK Custom.

You did not mention how fast you were averaging on the highway. Perhaps if you are in the 90 mph+ range that would be reasonable MPG...otherwise, something is wrong.

Two up, average 75 mph, I am getting 45-49 mpg.

Even pulling a trailer, whether in stop and go, or averaging 70 mph, I still do not drop below the 40 mpg level.

 

08 EGC - 38 -40 mpg with 1,600 miles on the clock. Mid range runs (30 - 40 mile hops) 50% city

 

I think it mainly depends on how you ride. I went from MD to SC kicking azz running about 80-90 MPH and I got ~30MPG.....Boy was I pissed. Talked to a few folks and they confirmed, "that's normal for that idiotic cruising speed".......So ,next trip I'll cruise 60-65 and it should be the normal 40-45MPG!!!!!


I'M HOPING!!!!!!!!!!!!!!!

 

See below for specifics. I regularly average 38-40 just riding around town. The lowest I saw was 34. On the highway riding 2 up(60-70mph) I get 44-46. I also have 6 speed which makes a big difference.

The key is tuning as Dalton said.

 

I ride an ULTRA... and most of my friends ride Ultras... and they all made fun of me for getting 41mpg.... they are all getting 47-50... I have an 06 and just had it dyno'd&nbsp\\; still 40mpg.... if i slow down i've seen it around 43

 

All I've done to my new SG is add V&amp\\;H Ovals and I'm getting 42 in town and 50 on the freeway at around 65mph. I don't want to change a thing.