Electric assist

We bought our first electric bike in 2002, when living car-free in San Francisco. Even after heavy modifications, it wasn't up to the task of moving heavy cargo and passengers up steep hills, so we set about inventing something that was. The result is Stokemonkey, patented in 2006 and still available today. We've learned quite a lot in the meantime, much of it the hard way. We stand ready to guide you in cutting through the hype and jargon surrounding electric bikes to find the best way to ride more and drive less.

While our expertise remains focused most sharply on assisted cargo and family bikes, which are special in their need to provide high power at low speeds efficiently, we are increasingly impressed with the elegance of today's best electric bikes and retrofit kits for longer range personal transport. We stock a tightly curated selection of "best of breed" products in this space.

We're not ashamed of electric assist the way some purist bike people are. But we do tend to be purist enough that we prefer electric approaches that build upon bicycle rather than scooter or motorcycle design. You'll get exercise, and you'll still be able to pedal home when your charge is gone.

BionX electric assist kits are the most refined and best supported on the market, with an unmatched long-term record of continuous innovation, not to mention solvency. Yes, I went there: the electric bike field is thick with the bodies of failed products and companies, who rushed products to market without either adequate engineering, financial backing, or both. People who own these products are mostly out of luck when stuff breaks or wears out. BionX is different, protecting your investment for the long term.

Silent, smooth, and cleanly packaged, BionX kits are ideal for longer range or higher speed commuting, even in hills. For heavy cargo applications, they work best if the hills are not too sharp or long, but building the motors into smaller wheels can help.

  • Proportional assist

    bionx electric assist

    Four levels that work seamlessly with you, offering a safe, natural-feeling ride.

  • Regenerative braking

    Bionx Regenerative Braking

    Spare brake wear on descents and recharge the battery (a little bit, anyway) as you ride.

  • Noise & vibration free

    Bionx silent electric assist

    Noise and vibration free motor, so your bike stays a bike and you can enjoy your ride.

  • Long range

    bionx long range

    Commute with confidence. Not only do the batteries provide long riding ranges, the lack of added resistance in normal pedaling means you can ride easily even past your powered range.

  • Lightweight

    bionx lightweight

    By keeping the systems as light as possible, your electric bike still feels like a bike.

  • Bike Types

    bionx bike type

    Easy retrofitting of almost all derailleur-ready bikes into e-bikes.