Extreme Electric Motocross Bike

The recreational vehicle industry and specifically trail bikes look to be set for a whole new range of possibilities in the near future as electric motorcycles become viable. Electric dirt bikes offer several compelling advantages over their current petrol-burning brethren, the most significant being they are completely silent. There is nothing more out of place in the forest than the bark of a four-stroke or the staccato rasp of a two-stroke – at complete odds with the tranquility of the wilderness and quite capable of spoiling the experience for those ten miles away, motorcycling without the noise is long overdue. For this reason, bikes are essentially banned from suburbia. Proof of just how far electric dirt bikes have come is the US$5,500 Drift XC bike from Electricross.

Though it only develops 19 bhp, the linear, predictable power delivery has broad torque available from the very bottom of the rev range and is absolutely ideal power for loose surfaces. The trick is in the weight though as the Neal Saiki designed bike is ultra light – just 140 pounds ready for riding compared to 240 pounds plus for a petrol engined bike of similar output.

There is no wet weight for an electric bike as there’s no petrol to burn, engine oil or even a gearbox. Saiki’s cross country bike designs have won numerous World Cup mountain bike titles and he recently landed Mountain Biking magazine’s 2006 X-Country Bike of the Year, so he knows his stuff . Before bikes he designed the first successful human powered helicopter (pictured), claiming one of the plumb aviation design firsts in history.

Inspired by the potential of the electric motor, Saiki has spent the last couple of years designing and building an electric cross country bike. Saiki found that motorcycle parts are generally too heavy (without the vibration, an electric bike can be built lighter) and bicycle parts were too weak for the forces he wanted to direct. The frame parts are all made from American-produced aluminum. Accordingly, every part had to be uniquely developed using computer analysis to optimize every component, such as the patent pending double diamond design that is lighter and stiffer than conventional swingarms.

Most of the parts such as the hubs, spokes, rims, chain and sprocket are custom-made, so almost everything had to be uniquely developed. Weeks of and all of Neal’s mountain bike experience was brought to the Drift’s frame design in order to create the lightest and most advanced electric motorcycle frame possible.

Despite it’s weight, this is no toy bike - it is full powered motocrosser without noise and opens up all kinds of backyard and semi-urban riding opportunities where noise is an issue due to impinging on the amenity of neighbors. If there were no noise, surely there could be no reasonable complaint providing permission was available to ride on the land being used. The noise issue could also impact where bikes can be used, enabling them to be given a section of inner-city parkland just for silent motorcycles.

It is an intermediate sized bike, but weights only 140 pounds with the power pack and 80 pounds without. The power pack is easily removable for transporting. The off-road suspension features 7 to 8 inches of suspension travel in the front and 8 inches in the rear. The fully tunable motor controller allows a custom power and speed map to be loaded to tailor the throttle response from “trail riding” to “racetrack” or anywhere in between. The power can be easily turned down for younger riders making the Drift suitable for a wide range of abilities. The controller is adjusted by hooking a cable up to your computer and running a software program that is provided. The software is easy to use and the controller can even record data as you ride so you can see where you’ve got the throttle open and where you haven’t.

A half power switch is also an option. At the flick of a switch the top speed and power is cut in half. This is perfect for beginner riders or for the occasional ride down the street in the bike lane. The switch extends the life of the battery considerably. With the reduced top speed the bike can technically qualify as a motorized bicycle and be ridden in the bicycle lane for commuting in most states. Check your own state laws at the DMV.

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