Two Wheeled Terror
Bob Burnside
March, 1997

Scott Cronk, founder of Electric Motorbike (EMB) has a strong background in business and electric vehicle development. With this combination plus his familiarity with companies in the field, he is more prepared than most to make the launch of his Lectra bike a success.

In an area of Sebastapol that is becoming known for its several electric vehicle makers, Cronk's business occupies space in a building behind a deli on busy Route 12, which has the potential to expand with his business.

The Lectra's prototype leans on its kickstand in Cronk's spacious warehouse. Its slightly "retro" look gives it a '60s personality. In April, assembly will begin on the production model. You'll be able to buy one at Golden Gate Cycle soon afterward for around $3000. The money you spend will buy some important new technology. The EMB-developed motor, a variable-reluctance creation with no brushes to wear out, boasts 92 per cent efficiency and 8 horse power at a maximum speed of 10,000 r.p.m. This compact powerplant was not possible until the computer technology was invented to provide the necessary precision to the pulses of electromagnetic power to pull the unique unwound rotor around on its axis. The only windings are found on the stator located toward the outside of the unit, providing optimum heat dispersion. A 4-to-1 gear reduction is further reduced 3-to-1 by the drive belt. 'Fat boy' tires and a feisty low profile give the impression that this machine is definitely more than a toy.

The bike's response is immediate and powerful as it jumps into action. Bill French who normally rides a powerful Yamaha YZS 750 says, "It is a weird feeling to sit noiselessly at a stop light. When I screwed it on, it would have beat my bike on acceleration. It really ripped up the hills. The seating position is as comfortable as a larger bike. I didn't want to bring it back."

The ample horsepower is reversed when the rear brake is applied providing electrical braking and also generating battery recharging power. This system offers full braking power when first applied and gradually reduces to zero electrical braking at 4 mph: a natural anti-lock feature. There is an auxiliary rear drum brake. The front disk brake is a dual- piston, floating-caliper system.

An onboard 440 watt charger brings the four batteries of this 24 volt system from 20 per cent to 95 per cent charge in two and a half hours. An optional 1.3 kilowatt model does the same in one hour. Current is usually limited by a signal controller to prevent strain on components. A boost button cancels this function offering 30 per cent more power for special situations like passing and hills. A state-of-charge meter gives accurate readout of energy/time remaining and there is a device that stops the motor at 20 per cent charge. It can be reset for an extra 5 miles of reserve power.

Cronk was working at GM's Delco Electronics when Ted Morgan of US Electricar offered him a job as director of business development for the small start-up. Morgan had been impressed by Cronk's book, Building the E-Motive Industry (S. A. E. 1995), which grew out of an MBA thesis project. US Electricar pro-vided Cronk with an educa-tion in a growing and then declining business. The company outgrew its ability to attract capital and has been restructured to a fraction of its former size. Cronk saw his opportunity, left US Electricar and started Elephant Motor Bikes in April 1995 with Rich Whisman, which became EMB. The Lectra has been carefully developed and tested resulting in a machine that will add a substantially different alternative to two wheeled transportation this year. The future may bring a more powerful model with a better range and a side car.

Cronk's long-term goal is to do a two wheeled electric circumnavigation of the world. Bob Burnside is managing editor of the Castro Star community newspaper in San Francisco.