Amazon.com : Eahora ACE Electric Bicycle for Adults 31MPH 1000W Peak Electric Mountain Bike 48V 16A 60Mile 500W BAFANG Mid Drive Motor 27.5" DH Lockable Fork Ebike Shimano 9-Speed Full Air Suspension
CeramicSpeed Driven on mountain bikes – a drivetrain without a chain and a derailleur | ENDURO Mountainbike Magazine
The Lal Bikes Supre Drive could kill the rear derailleur and gearbox - BikeRadar