Weight Implications
Elaphe representatives told me that, despite the extra motors, its version of the car weighs just a few pounds more than the standard one. The stock brakes are retained, but the suspension is replaced by bespoke KW units, calibrated to handle the extra weight in the wheels.
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Yes, there is additional unsprung mass here, with each motor weighing something on the order of 60 pounds. That must necessarily ruin a car’s handling, right? “The top test drivers in the top performance OEMs would disagree,” Elaphe CEO Gorazd Gotovac said. “From my perspective, that’s enough for me.”
Gotovac admitted that, for premium luxury machines, the extra weight in the wheels would potentially cause complications in ride quality, but nothing that can’t be addressed with more advanced suspension damping. He claimed the idea of in-wheel motors reducing handling performance is a myth. “High-mu, low-mu, on tarmac and on ice, we prove that every day to OEMs,” he said.
That, unfortunately, is one area of evaluation we cannot comment on. While your average frozen lake is bumpy and rough, the test courses we sampled in Sweden were groomed to be ultra-smooth.
That extra mass hanging out in the wheels must surely have some negative implications, but Gotovac said they’re far outweighed by potential positives. By moving the motors out to the wheels, you free up room within the chassis, meaning space for bigger batteries, more cargo area, or just overall better packaging. Even this Ioniq 5, which typically has just a tiny frunk, instead had a massive empty space under its hood.
But by designing a car from the ground up to use these motors, Elaphe says cars can be lighter, too, by switching to smaller brakes and doing away with reduction gearsets and differentials, which also sap power. Designed in this way, Elaphe estimates cars could also be upward of 10 percent cheaper to manufacture when you factor in the smaller batteries required for lighter-weight, more efficient cars.
And what about servicing the brakes trapped behind those motors? Once you take off the wheel, there are three exposed bolt heads. Loosen those, replace them with pins to hold the motor’s rotor and stator in place, then unplug the motor and lift it off. Easy.
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That’s not something you should need to do too often, thanks to the motors doing much of the braking. Still, Elaphe designed its hub motors to fit over even big sports brakes, up to nearly 14.8 inches in diameter—and stepping up to 15.7 inches for the company’s hypercar-spec motors.
