The electric car has remained problematic for engineers over the years, in no small part because of its size. The battery power required for a vehicle weighing over a ton (907 kilograms) is daunting, to say the least, and there are serious issues with power and cruising range before recharging becomes necessary. The motorcycle, however, is a different -- and much smaller -- beast, and it is there that much of the progress in electric transportation has come about in recent years.
Even within the motorcycle class, electricity has found a niche. Electric dirt bikes are generally driven a short distance, are lightweight, and rely more on bursts of power than long-term cruising speeds. Moreover, the use of electric rather than gas-powered engines eliminates all of the exhaust emissions and most of the noise that has ruffled the feathers of outdoor lovers who see dirt bikes as brazen interlopers into their tranquility.
Neal Saiki, one of the pioneers in electric dirt bike manufacture, came up with a vehicle weighing only 140 pounds (63.5 kilograms) with a two-battery power pack installed, roughly half the weight of a gas-powered dirt bike. His creation went on to capture a number of important races and earn instant respect in the dirt bike community. Part of the appeal to riders was the use of multiple power packs to avoid having to wait for re-charging. Nevertheless, an electric dirt bike can only travel about 40 miles, or two hours trail time, before re-charging becomes necessary.
One interesting feature of some electric dirt bike models is a "half-power switch" that cuts power in half simply by the use of a switch. This is ideal for beginning riders or city travel. On full power, according to company literature, Saiki's Zero model can go from 0 to 30 mph in under two seconds and reaches a comparable top-end speed as gasoline-powered bikes.
As with many innovations, the electric dirt bike is more expensive at this stage in its development. Part of this is because some of the parts have to be specially made -- at this point, it is expensive and difficult to simply convert a standard bike to electricity. Also, most of the companies producing the electric dirt bike have been entrepreneurial start-ups like Saiki.
In December of 2008, however, Honda announced plans to develop its own electric motorcycles, which would presumably include an electric dirt bike. The company said it hoped to have one available in two years. Another firm, KTM, already has a prototype.