Gas Mileage

Most of my bikes have gotten around 45 mpg. My R3T gets around 38 mpg. Motorcycles now days often have engines that rival compact car engines. Heck, Rockets have a larger engine (2.3L) than most compact cars and a lot of the midsize cars. Most of the bikes that have these larger engines (1500cc and up) are the larger touring & cruiser bikes. But, even the heaviest bikes only weigh around a third of what a car weighs, if that.

A lot of compact cars get 35 mpg and even a lot of the midsize cars get into the low 30s. My Honda Civic got close to 38 mpg. If memory serves, it had a 1.6L engine. There are tons of bikes with that size engine. Considering they have much less weight to haul around, I would think they could get 60 mpg easy.

I'll talk what I know. The R3T, according to Triumph specs is 2.3L, puts out approx. 110 hp and has a 154 lbs of torque. The dry weight on the bike is 788 lbs. I weigh 150 lbs so let's say the bike probably weighs 1000 lbs give or take a pound all loaded and ready to ride. That's probably a third of what a car weighs. In addition to this, they also have less friction on the road as they have 2 less tires on the road. I won't address tire size because most of the larger bikes have tires that are close to the size of a car tire (compact cars, anyway).

Don't get me wrong, I'm not complaining. Motorcycles get good gas mileage, but I don't understand why they are, seemingly, so inefficient. I would think they would get a lot better than they do.

There is an article in the Cruiser magazine this month about the same thing. they lay it all to drag and turbulance. things like the exposed wheels flat head lights, your arms, mirrors and blinkers.
Drag factor on your body with flapping coat tails and even rolled up sleeves are all a factor. That's their take Im not sure I agree I think its the drive it like ya stole it syndrome.

Gunshots is onto something. If you look at newer cars you are going to see (What Nissan called) Hardbody styling. No antenna, door handles recessed, no rain gutters, a flush gas door and so on. The car is almost smooth. This all cuts the drag. Drag goes up exponentially with speed. I don't know the exact formula but its mind boggling.

Also... the Rocket is as aerodynamic as a barn door. Especially mine with the Fleetloaner and the taller screen. Even with that I get mid to low 30's and for the performance that's fine by me