E-bikes and a 12-year-old's death

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From the lawsuit...edited italics and bold

48.Specifically, Rad designed and manufactured the RadRunner electric-motorized bikes, including the Subject Powerbike, with at least two design defects. First, Rad chose to use disc brakes in conjunction with a quick-release mechanism for detaching the front wheel. This configuration has been a known safety hazard in the industry for at least a decade, even when used with non-electronic bikes. This is because the front disc brakes have calipers behind the fork blade, and when the rider pulls hard at the front brakes, it generates a powerful force and friction that causes the quick-release mechanism to unthread, loosening the wheel and causing it to wobble and shake, and in some cases, causing the wheel to come off entirely mid-ride. Even one hard pull at the brake, especially during a steep downhill ride such as here, is enough to cause these two components to interact with each other in an unsafe way, causing a loss of control, which of course causes injuries and deaths. This is a known safety hazard in the industry, and Rad chose not to use the safer alternative mechanism for releasing the wheel, called a “through axle” mechanism. Through axles are universally used in connection with disc brakes in motorcycles for this reason. However, bicycle manufacturers continue to use these unsafe quick-release mechanisms with front disc brakes in lower-end bicycles, because the quick-release mechanism is cheaper to manufacture than the through-axle mechanism. Rad knew or should have known that this was an unsafe and defective design, but Rad chose to implement it anyway to increase its profits.

49.This design defect - the combination of the quick-release mechanism and the front disc brakes - was a substantial factor in causing this accident and Molly Steinsapir’s death. After the accident, the rear brakes of the Subject Powerbike were worn thin and the front wheel was loose and wobbly. The Subject Powerbike was purchased new approximately a month before the accident. It was assembled by Velofix on January 7, 2021, and therefore had been in the Greens’ possession for just over three weeks on the date of the accident. The brakes were intact, and the wheel was not loose when Emerson and Molly began their ride on January 31, 2021. They rode to the top of the hill on Enchanted Way, riding up a steep incline they only achieved in the first place due to the Subject Powerbike’s powerful motor. On the way down, Emerson tried to control their descent by using the rear brakes, but that only succeeded in wearing the brakes out. As the Subject Powerbike continued to pick up speed, Emerson pulled hard on the front brake, but because of the design defect of the quick-release mechanism used in connection with the front disc brakes, her hard braking caused the quick release mechanism to unthread. The front wheel loosened and became wobbly, the bike began to shake, and Emerson lost control of its steering.