If scooters could talk, they'd probably spout the late comedian Rodney Dangerfield's line about not getting any respect. No one casts admiring glances their way. In fact, some bikers even seem to sneer at them, but that hasn't stopped sales from rocketing through the roof.

In cities such as Tokyo, where parking and operating costs make car ownership impractical or impossible for many people, scooters are the next best thing. They have car-like qualities — good protection from the elements, cavernous built-in storage and automatic transmissions; but running costs are cheap thanks to decent fuel economy, low annual taxes and — if they're 250cc or smaller — no pricey biannual vehicle inspection.

With scooters accounting for a whopping 60 percent of sales of bikes 250cc and bigger in Japan, Yamaha, Honda and Suzuki duke it out year after year for a larger share of this lucrative market. And in gizmo-crazy Japan, the key to sales success is constant innovation.