Motor & Gear

Finally everything was ready to combine motor and the customized gear! First some words to the gearbox: Electric motors in general do not need a gearbox with multiple gears like ‘old fashioned’ combustion engines. But when using a fast turning machine like the hybrid syncronous motor made by Brusa, a transmission is necessary. The motor has a maximum speed of 11’000rpm and maximum torque of 220Nm (up to 4000rpm). The gear will scale down the speed and scale up the torque as we learned in physics class. Together with the gear ratio of the differential gear we can calculate the scale factor between motor speed and wheel speed. Using the original 2nd gear of the Syncro-gearbox we get a top speed of about 120km/h which is even a bit more than what you really want to drive with this car. Together with Toni from Technikschmitte we decided to keep the original 1st gear as our ‘offroad gear’.

2 thoughts on “Motor & Gear”

  1. Hi Guys

    Pretty amazing stuff here! As a Syncro Owner by myself i got two questions:

    – a lot of Syncros with conversed Engines suffer from Gear defects, especially the 4th trough high speeds. Im not too much into the internals of the Gearbox but dont you think this gets even worse if you use the second Gear which might be somewhat less durable by design?

    – my Dream is a Syncro with 4 independent E-Motors on each Wheel, get rid of all the Gearbox Stuff and control things like differential lock trough Software only. Have you thougt about something like that or is this completly sonsense?


    1. Hi Andri
      Thanks for your comment. We heard also that the syncro gearbox might be critical with respect to endurance. But we will not put much more torque trough it than before and due to the electric drive there will be a much smoother torque than with a combustion engine. The critical issue will be the rotational speeds. As the e-motor goes up to 11’000 rpm this will be interesting in case of heat dissipation. We removed all unnecessary gears to minimise frictional losses and have more volume for oil. Btw. Frank has run his e-Bulli T2 in 2nd gear already for about 40’000km with no problems so far. The 4-motor syncro would be a cool thing indeed, but this would lead to a massive engineering, because you would need to accommodate the motors close to each wheel, hence that would result in a major redesign. For us, this project is challenging enough already. But who knows, maybe version 2.0 …

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