Look at those disk brakes
The disc brake option for the Heinzmann adopts a similar large diameter solution, and large diameter is best for braking force of course. Trouble is the vulnerability to damage on thin bike discs, especially when exposed like this. The slightest buckle and the bike is out of action and unrideable.
I still don't understand why Matra have adopted the Tidal Force design. It's completely illegal as an electric bike anywhere in Europe and if used by anyone as a bike, the insane performance will attract unwelcome police attention to all e-bikes. It won't even meet the high speed class regulation in Switzerland and Germany.
If used legally with registration, number plates, insurance etc as a motor vehicle, I'm sure most would prefer a petrol or electric moped/scooter, particularly as they'd have to wear an approved motor cycle helmet when riding it, not welcome when pedalling a bike!
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