I noticed that Harley advertises 54 highway MPG for the Ultra and other models. However, everyone here seems to average anywhere from 35-45 MPG on the highway. I understand that the 54 MPG estimate is based on ideal conditions, but 40MPG is a looooong way from the advertised 54 MPG!! Is it actually possible to get 54 MPG on the highway if you ride 1-up and average 65-70 MPH in 6th gear on flat ground?

 

That would average out to 44.5 MPG which is what my 07 stock was getting (48) beforeI started messing with the engine and fuel management. Then it wet to 30 or so, but ran strong and cool.

 

I don't know about 54 MPG , but I often get 52 MPG on a Canadian gallon riding the way you described. This is on a Road Glide with a tourpack and 3" over stock height windshield.
54 MPG is probably not realistic , but you should be able to get 46-48 MPG on a US gallon

 

on my '07, I saw HWY mpg range from 48 --> 60+.

My combined mpg was ~46 city/hwy. I had stock pipes through 15K miles, then put Rinehart TD's on and my mileage did not change over the course of the next 3300 miles before the bike was totalled as a result of my collision with a bundle of silt fencing some jackass dropped off of their vehicle.

I'd would agree with previous posts whereby the MoCo mpg rating is under 'ideal' conditions. Each bike will vary, depending on how it was broken in, how the rider actually throttles the bike up, weather conditions (wind, no wind) etc.

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KoalaCowboy
KoalaCowboy

 

On our trip to sturgis this year I got anywhere from 45 to 52 on my '07 road king. I didn't test it on the way up there but I did on the way back. I got 52 on two different tanks with a full load of gear. I was leading and had the cruise set at 70mph (which is about 66mph) on fairly flat terrain. I'm pretty happy with that.

 

I don't get anywhere near 54 mpg. I'm lucky if I get 40 mpg. However I do ride 2 up most of the time and run somewhere around that 75 mph mark. On 08 Ultra.

 

Only if you weigh about 120 lbs dripping wet and only drive down-hill.

 

I have a heavy hand on the throttle and with all mods done I get about 45 mpg combined total for the tank. As for hwy vs street i dont get a chance to test the difference.

 

My mildly built TC Road King gets about 35+mpg on the slab but I roll about 80mph and I'm not a small guy. (6' 5" and 300lbs).
I could get much better mileage if I de-tuned it and slowed down to 65 mph but I finally got it where I want it so I'll live with it.

 

there is an astericks (*) next to the 54 mpg claim. If you read the fine print it says under ideal laboratory conditions which means, in their R&D facility with the bike on rollers with no wind resistance, steady throttle, simulating perfectly level terrain. As for me, would rather have wind in my face instead of standing still. The wind resistance alone can account for several miles per gallon - easily dropping it below 50.