January 2011, Saint Francis, Wisconsin: GBNpro commissions the conversion of a Rans Screamer (tandem recumbent) with the BionX electrical power system. Two technicians from South Shore Cyclery, in Cudahy, Wisconsin; Steve and Taylor, researched all available conversion kits and chose to install BionX over many other systems. BionX offered more versatility with their kit, more so than the other manufacturers in a number of important areas. They provide a baseline 350 Watt electric hub motor which varies output as needed from typically 250 - 500 Watts from their propriety 37 Volt Lithium rechargeable rack mounted battery. The battery slides in/out the rear rack with key lock for security, provides it's own rear LED tail light and custom added front LED headlight. These are both powered from the 37 Volt main drive battery. Steve and Taylor made a few modifications to integrate all the electrical devices and wiring harnesses.  Top speed is 21 MPH (set by law) with typical average speeds of 9 - 14 MPH. On the trail's steepest grade it'll do 11 MPH up hill, against the wind with two adults on board. That's without pedaling. If you wanted to maintain greater speeds, one would need to pedal. Imagine that, pedaling a bike?

While pedaling one has the choice of using four (4) assisted power levels or four (4) generation levels. Power assist really kicks up at levels three and four where you can run up to your highest speed gear selection and maintain your greatest bike speeds. Doing this, one can still get some exercise, but it's going to be double your average speed. The scenery will be going by and you'll be glad you're wearing a helmet. All the regeneration and assist gets dished out by automatic torque sensors built into the hub motor. The four different generation levels are literally a real drag ;^)  These generate electricity for the recharging of your system battery while on the fly. Obviously recharging is easier from the wall outlet, but this option recaptures energy while braking and going down hills. This regeneration allows longer trips due to this energy regeneration/recapture, so you don't flatten your charge too quickly. When the battery is flat you still have a regular bike under your seat - so all is not lost.

The Rans Screamer needed a few other custom modifications accomplished by the technicians at South Shore Cyclery. The rear wheel drag brake, normally controlled by the stoker, gets removed when the 26" hub motor assembly replaces the existing rear axle/wheel. Because the motor is also a generator, drag braking is now accomplished automatically when the Captain uses the conventional hydraulic brake handles. Steve and Taylor developed a custom magnetic switch on top of the hydraulic brake to engage the generate side of the hub motor while braking. The generation of electricity commences slightly before the hydraulic brake shoes touch the wheel rim. So, feathering the brake lever leads to drag/regeneration before one actually needs to use the friction brakes. This is a real benefit for recharging the battery, not wasting energy or wearing out break pads.

Controlling the bike takes a few minutes of use before one becomes confidently functional. The bike can be ridden as a simple bicycle, pedaling and shifting between gears with/without electrical assist. As long as the riders don't have the bike in regeneration mode, the red thumb trigger near the shifter acts like a simple throttle. The bike is "safetied" in that one must be moving one-two miles per hour before the electrical system becomes active. This prevents someone from hitting the throttle from dead still and having the bike take off with nobody on it.

If one doesn't provide enough human power, the "Screaming-BionX" can always be plugged in for a complete recharge in a short time.  From completely drained to full charge takes two to three hours, or typically twenty minutes to an hour for a top off if you're not completely drained.

So far in testing we have made thirteen to fifteen mile zero peddle trips using only the electric motor off the battery. These short trips were conducted in typical Wisconsin Spring weather. Strong breezes off 35 degree (F) Lake Michigan water and ambient temperatures between 37 - 48 degrees (F) with both lights on. These conditions are not optimal for battery life or recumbent rider warmth. The trips used nearly 70 percent of the battery charge under these conditions. When one uses the electrical system to assist up hills and for greater speed in the flats with mixed regeneration when coasting or going downhill, only about 25 percent of battery charge was used under the same conditions. Peddling also helped to stay warm! We estimate mixed use would be optimal for health and range for both sources of energy ;^)