In 1997 I visited a pedicab manufacturer who was experimenting with an electric-powered version of their pedicab (bicycle taxi). From previous projects, I knew that electric vehicles were impractical in terms of range, recharge time, and weight; the only advantage I could see was their attractiveness from an in-use emissions perspective (ignoring their environmental impact during manufacturing and recycling/disposal).  In the case of the pedicabs, the electric motor and batteries added a massive 130 pounds to an already heavy vehicle.  Most of this weight was due to the low storage density of batteries.  In fact, most common form of batteries, lead acid, have a storage density of about 35 Watt-hours/Kilogram (more expensive batteries such as Lithium Ion, only store about 150 Watt-hours/Kilogram) while the energy stored in gasoline is 12,000 Watt-hours/Kilogram.

So I thought to myself, “How do you power a bicycle with a clean gasoline engine?”  I continued to think, “Would it is possible to design a bicycle wheel with a gasoline engine built right into the wheel?”  The trick was to have the entire engine, geartrain, starter, geartrain, and starter be so thin that the whole assembly could spin between the forks of a standard bicycle.  This spinning assembly (i.e. wheel with engine) could be cooled because it spins and not by a massive flywheel with a fan.  In addition, I sought a solution that would allow anyone to install it on most bicycles and be easy to use.

Thus began an interesting journey of discovery and experimentation.  From the earliest prototypes, we progressed from stage to stage over a period of several years.  In 2002, I filed a comprehensive patent, and just a year later in 2003 we founded RevoPower.  Therefore, in 2003 I was able to go to work full time on the project.

The technical challenges and obstacles we faced are too numerous to mention – keep an eye out for my book!  However, those of you who are technically minded (or have engineering training) can see from the photographs that the important challenges involved delivering fuel to a rotating engine, throttle control through the axle, and miniaturization of ignition system.

What we will deliver in the next year is a reliable and practical motor-assistance device which will reduce the world’s dependence on oil, remove congestion from crowded roads, and transform third world economies.  I look forward with great anticipation to seeing fleets of RevoPower bikes heading down roads across the world.

Thank you for visiting our website. I hope you share our passion for this product.

STEVE KATSAROS
CTO, RevoPower