Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
I tend to agree, since both my Airhead and GoldWing get better MPG on slower, rural roads, in 2nd thru 4th gears.In many cases, the best volumetric efficiency occurs at or near the torque peak (not the horsepower peak).
Putting along at 1100-1200 rpm in top gear is not in this range, and the engine would surely protest.
On my bikes, 45-50mph is the sweet spot. I can average as much as 58 mpg 5th gear at 51mph.
Current R1200RT, for example, blow away Airheads as regards fuel economy.
I've found that the mileage I get can vary by up to 5 mpg or more, depending on the blend of local gasoline. For example, I live in Boise, Idaho, and when I take a ride out of my area (150 to 200 miles) - either west into eastern Oregon or south east to the Salt Lake valley the fuel I buy there will give me a 3 to 5 mpg increase. On cross-county trips I've seen a lot of variation as well, so always watch my fuel gauge after every fill-up to get an idea of what kind of mileage the last gas I bought is giving me.
One variable often overlooked is altitude. I usually get better mileage at higher altitudes.
The altitude difference between Boise and Salt Lake City is only about 1,500 feet. I wouldn't think that would make a huge difference and gas mileage. Some but there must be other factors.
I've ruled altitude out as a factor, as I get the mileage boost consistently across different altitudes as long as my riding style and road conditions are similar. That GPS altitude feature is very handy.
On our bikes Altitude is one of the data fields always displayed. An old habit from riding a K75 with an altitude "plug" which was actually a handlebar switch. Both here and in New Mexico when we had a condo there we went up and down enough to need to know when to switch the plug in or out.
I've had the altitude plugs, switched, on my K's, switching them on and off at 5,000', but really never noticed a difference in mileage or performance. Something I haven't seen much discussion about here is the winds you encounter impacting mpg. I know from fighting a head wind or quartering cross wind heading west across the plains I've watched my mileage drop.
My '85 K100RS w/EML, generally gets around 35 mpg, running 70 mph, but in it's early years, it dropped to 17 mpg. That was definitely speed related, when my friend and builder Ozzie decided to take it to Mexico and race it in the La Carrera road race, in '87. He took the boat off and modified it with a road race boat. He and his son, his monkey took first in the sidecar class, and most of the solo bikes. After Ozzie's passing, I asked his son what he remembered about the race. He said that they were never under 100 mph, much of the time over 120, passing solo bikes on the outside going around corners, and running the tank dry at 100 miles. They finished in the top ten, beating all but nine of the roadracing solo bikes. Road racer Larry Coleman, racing a roadrace hack, commented that they went around us like a land rocket.
View attachment 82470
Yep, speed related...
View attachment 82471
Excellent story! Thanks for sharing.