Originally Posted by
Winfried
Incidently, several manufacturers* offer a front hub motor to turn a regular Brompton into an e-bike.
If the original fork is strong enough to withstand a hub motor with a torque of about 50Nm, wouldn't it be able to also take the force from a disk brake?
If all it takes is finding a competent LBS to weld a disk caliper adapter on the right side to fit the Brompton's folding, getting the kind of 74mm wide hub I mentioned above, and building a wheel… it'd be a nice upgrade.
Of is the effort from a disk brake very different from a hub motor?
Braking forces are much greater because the acceleration is much stronger. Your braking from speed in just a couple of seconds. That is a lot force. F=MA where A is the change of speed with time.