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Drive Considerations
If a target maximun speed for our rear wheel drive is to be 60mph (926rpm for Insight 165/65R14 Bridgestones) for instance and the maximum rpm for the Etek motors is to be 4000rpm, the drive reduction ratio is about: 4000:926=4.3:1 (.23) If we keep with using the 14m motorcycle drive parts for our final drive, this ratio is not obtainable directly with any of the available 14m belt drive components as far as I know, so a two step reduction will be needed. This could consist of two pairs of pulleys or a pair of pulleys and a gear box.
The Etek motor is not enclosed so we will need to enclose it and ventilate it or place it where it is protected from splash and dirt contamination. If we keep the final drive as low as we can with ample road clearance and the motor up high and dry, we come up with something that resembles an electric outboard motor. (Briggs & Stratton did sell such an electric Etek outboard motor. If we could obtain a pair of these, our drive would be almost complete, however, these used a brush type Etek motor and I don't think they developed 6hp and they had no need for a neutral clutch or reverse gear.) For our purposes, it is better for us to find a suitable outboard lower unit and adapt our Etek motor to it. Also, we can take advantage of the forward-neutral-reverse clutch that is built into most lower units. We will need that neutral to lessen the drag of the unit when it is idle.
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