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0 pointslelanthran1y ago0 comments

> If the weights are listed on the are to be believed, this shouldn't be an issue. It says 40 kg for a 21" wheel. A quick Google is telling me that a regular old steel wheel from a truck of the same size is around 50 to 80 lbs (23-36 kg).

I'm skeptical; They say 40kg, but I think that's just for the motor, not the entire wheel. I working off the (maybe incorrect)[1] assumption that the 40kg doesn't include the steel/mag rim and the tyre.

As far as a 21" standard mag wheel, the tyre alone is around 12kg, so quite believable that a standard wheel with tyre would weigh maybe 30kg. However this still means that putting a tyre on a 40kg wheel is going to take it to +52kg.

[1] Just the minimum metal and rubber needed for a 21" wheel to maintain its shape and structure should be around 30kg. Maybe this motor is structurally round already, so doesn't need any rim to reinforce it?

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johnwalkr1y ago

I think it still needs the wheel, and all the related parts in the middle like an upright/steering knuckle, which probably cancels out any mass of the motor that is acting as a structural part of a wheel. Other things like brakes would still be required. These should allow for regenerative braking normally the braking torque of a motor is nowhere near the acceleration torque, plus they don't mention braking function anywhere so it's safe to assume there's no special performance there. In all, I would assume for now that a 40kg motor would add approximately 40kg to the overall wheel mass, possibly even more. It would be interesting to see if there's a concept for an inboard version of these motors and compare to others.

m4631y ago

A regular wheel is about 12kg bringing wheel+tire to ~25kg

At these weights, I suspect the vehicle won't handle as well as a vehicle with the motor offboard.

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