The BionX Energy Management System can be installed on most bicycles by replacing the rear wheel with the BionX motor-wheel. The BionX system can be retrofitted on all bicycle models: road, mountain, tandem, folding, recumbent and recumbent trikes up to 27 speeds.

• Wheel sizes available: 700c, 26", 24", 20", 18" (Birdy)
• Standard drop-out: 135mm
• Installation with threaded free wheel
• Disk brake compatible
• Black rims and black spokes available upon request
• If the battery does not fit on the frame, it can be installed on a carrier.

This what ExtraEnergy.org has to say about Bionx:

Extremely efficient, a pleasure to ride and very simple to install – the answer to electrification of your dream bike. Rating 2009: Very good

Advantages & Benefits

• Gives a Bionic sensation to the rider.
• Evens out all level of cyclists (friends and family) and allows them to ride together.
• Allows long distance riding with minimum level of fatigue.
• Adds to your pedal strokes and eliminates dead spots.
• Can be used as training for the faster cyclists due to the generative mode.
• Can be used as an interior and exterior workout machine.
• Gives the sensation of riding with a super light bike (level 2 eliminates the weight of the bike).
• The motor-wheel is quiet and requires no maintenance.
• Being light, it can be taken anywhere.
• Can be easily installed on YOUR bike.
• The battery can be recharged while braking or going downhill.
• Allows you to defy the hills, the wind, and even a faster cyclist.
• Is a great mode of transportation to get to work.
• The Bionx control console includes a programmable anti-theft alarm and a thumb throttle for instant acceleration.
• Gearing installation is easy with a threaded freewheel.
• The BionX system can be installed on a tandem, folding bike or recumbent; any bicycle with a standard shifting system.