Stokemonkey

Makes It Easier

An electric motor linked to existing bicycle gears turns any bike into a sell-your-car-already vehicle.

By Rick Polito

TODD FAHRNER DOESN’T WANT TO MAKE IT

easy for you. But he does want to make it easier.

A bike-centric, car-less existence has always been possible for strong people with strong feelings, but with Fahrner’s Stokemonkey kit, it gets easier. With an electric motor linked to existing gears and an Xtracycle hitchless trailer to extend the wheelbase and cargo space, the Stokemonkey scenario turns any bike into a sell-your-car-already electric vehicle.

A committed bike commuter and car-free thinker, Fahrner knew his human-powered bikes could do anything a car could do, and better, but with parenthood making the hills that much steeper, he needed a little help. He already owned an Xtracycle-equipped bike. The hitchless trailer concept transforms commuter bikes into cargo bikes, but they aren’t designed for parents living in San Francisco.

“The cargo capacity was great, but we couldn’t really make full use of it in on human power alone, not in those hills with these knees as we approached 40,” says Fahrner, who now co-owns Clever Cycles out of Portland, Ore.

So he took the Frankenstein approach to the best electric bike he could find, grafted on some extra gear range, and rode it into the ground for 5,000 miles. What arose from the scatter of bike parts was the first true Stokemonkey.

THE POWER OF THE TRANSMISSION The secret of the Stokemonkey is the transmission. Many electric bikes utilize in-hub motors; some even have rollers applying power to the tire. Fahrner’s design mounts an electric motor and 36-volt battery pack onto the Xtracycle-configured bike. The motor is connected by a chain drive to

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an extra chainwheel on the left side of the bottom bracket, boosting leg power and allowing cyclists to take advantage of a triple crankset’s gear range. As a result, Stokemonkey owners can pull hundreds of pounds of passengers and cargo up the steepest hills, or zip on the flats in high gear.

That gear range gives the Stokemonkey tremendous capabilities. Bill Manewal is a homecare nurse in San Francisco. At 63, he was looking for a little oomph to maintain the no-car commute. One ride with Fahrner was all it took. “He put me on the back of his [bike] when he was living here in San Francisco and rode up this really steep hill,” Manewal recalls.

Now a typical day means dozens of miles riding the hilly neighborhoods to visit patients. Speeds are upward of 25mph on flats and a good clip up steep hills, even with cargo. Manewal once delivered an industrial air cleaner to a client’s home, by bike. “I ride usually between 25 and 35 miles a day, and it costs 8 cents to charge it,” Manewal says. “It just levels out the hills.”

The Stokemonkey kit with the motor, mount, chain, crankset, charger, throttle, and battery costs $1,350. The owner will need an Xtracycle-equipped bike. Xtracycle kits start at $244 and can be bolted onto any bike. You’re not shopping for a featherweight racer here. A beater will do, but disc brakes are a good add-on. A clever parts hound could roll down the driveway for under $2,500, a lot less than even the crankiest secondhand car.

Fahrner says pre-installed, street legal Stokemonkey bikes are coming soon, but for now you have to do it yourself. He describes the required mechanical aptitude as “not much,” but a Stokemonkey builder should be comfortable with basic

Photography by Todd Fahrner