If you own a mid drive, here's some IGH options and warnings | ELECTRICBIKE.COM
Shimano Nexus SGC30007R 7Speed Internally Geared 36h Rear Hub *** You can find out more details at the link of the image. This i… | Shimano, Nexus, Vintage bicycles
Nexus 7 friction
Shimano Nexus 7 vs Nexus 8 [Gear Your Ride Up] – Turn Cranks