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Key role for Apex in Electric recumbent bicycle

Earlier this year, we informed you of the successful record attempt of the Human Power Team from the University of Delft, and the role of our gearbox in this design. Electric bikes are totally hot right now. This is usually a normal bicycle with an auxiliary electric motor, pedaling supported by an electric motor and thus you get easy high speeds. Richard van Ellinkhuizen cycles every day 64 km’s to and from work, and wanted to reduce its dependence on the car. But since he could not find his ideas in existing bicycle designs, he invented, designed and made his own pedal-supported bicycle, with which he already drove over 30,000 km!

One of the requirements of Richard was that he did not make use of fossil fuel like traditional engines. Therefore, he chose besides his own legs, for an electric drive. The combination provides a top speed of 50 km/h! An electric drive has a number of advantages over an internal combustion engine :

• Quieter
• Environmentally – friendly
• Low operational costs ( factor 100 to 200 lower)
• High efficiency
• Fewer moving parts and wear

The choice of various parts was not really difficult according Richard. The electric motor is fed by a battery with a capacity of 643Whr and contains 13 prismatic LiFePO4 A123 cells, and although the electric motor can deliver 2100 watts at 9.000 rpm, it is restricted to about 850 watts peak power at 7.500rpm. The electricity consumption is around 600Whr per day .

His real challenge came in the choice of a gearbox:

“After the chain reduction was finished, I searched the internet for a suitable planetary gear reduction. I had quite a lot of trouble with this : I searched all corners of our planet and emailed many manufacturers before I found a gearbox which met my requirements. My design requirements were roughly 15 Nm required outputtorque and input speed +/- 8 to 9000 rpm with a low weight and as small as possible. The AER50 of Apex Dynamics was the best fit.”

After 20,000 km’s Richard has taken the whole bike apart for inspection, maintenance and cleaning. He was not surprised to see small wear on the sun gear, as this is quite normal after so many hours at a continuous mode. He added since then another 10,000 km’s without problems with his bike!

Apex Dynamics runs faster, this is also true for electric bikes !

Press release December 18, 2013, Helmond