Speed first. Part second. Maker if you already know the name.
3 kits · Friction drive
Gboost
Gboost · 25 km/h
Maker list
HillTopper
HillTopper · 20 mph
Rubbee
Rubbee · 25 km/h
Compact European drive listed at 250 W with packs from about 251 to 441 Wh.
250 WFriction drive25 km/h
American friction drive. A roller on the rear tyre, clamped near the seat stay.
750 WFriction drive20 mph
Lithuanian friction drive. A powered roller presses the rear tyre. Lift it off and the bike is a bicycle again.
ConvoKits