For better/worse, much more automotive tech has been showing up in motorcycles in the past ten-ish years. Much of this has been driven by EPA and EU emission standards. EPA was pretty hands-off from 1980ish thru 2006 when they dropped the hammer which essentially requires catalytic converters for the larger bikes to meet.
http://www3.epa.gov/otaq/regs/roadbike/420f03044.pdf
In some sense, motorcycles are getting off easy, considering they are allowed to emit 10-20 times the controlled pollutants per mile than a new car. OTOH, the size and weight constraints present with bikes, would make meeting car standards impossible. Meeting emissions with diesel powered motorcycles would be doubly impossible for the same reasons.
While scooters and small bikes can get 75ish mpg pretty easily around town while meeting EPA requirements, all bikes run into an aerodynamic brick wall at highway speeds where one's lucky to get 50 mpg.
Too, while things recently have been changing, relatively few motorcycles are used daily for commuting in the USA, so the small-bike market here is limited. Honda probably makes more money on one Gold Wing sale than 20 of the ~250cc class. Cruisers and sportbikes being the most profitable here, higher-tech development has been largely confined to increasing horsepower and adding doodads, often well beyond the point of sanity. (How about a Ducati 1298(cc) weighing ~420 lbs with 205 hp, for example?) My 1978 Suzuki GS1000 (994cc) gets 43 mpg, my 1998 Ducati ST2 (944cc) gets 43 mpg and you'll struggle to find many large bikes that do any better today.
However, perhaps that is changing. Honda seems to be doing pretty well with a series based on 2 cylinders of a Fit engine which increases average mpgs by about 50%. It's a significant modality shift though, and it remains questionable whether these truly modern motorcycles will be accepted well enough to be widely adopted.
2012 Honda NC700X Review - Video - Motorcycle.com
Today
Other popular topics in this forum...
