9-speed freewheel on rear hub motor?
I'm playing with the idea of converting my Surly long haul trucker into a mid-high powered electric bike. It's set up as a 9 speed right now, and I'd really hate to switch out the gears.
Do you know of any rear hub motors (or complete kits) that allow a 9-speed drivetrain? Preferably a 450W+ motor, I want to be able to cruise at 25-30mph on flats with significant pedal assist.
I think that you will find with motor assist that you will not need as tight of a range of gearing. I think that the most you can stuff on a rear hub motor is a 7 spd at this time? Anyway it is all about the big ring with mab's anyway. Keep in mind that top speed allowed for e bikes is 20 mph nationwide also. If you want to go 30 legally you will need to take a look at a gas conversion because they are allowed up to 30 most places.
Bionx offers a 9-speed freewheel option with they're kits. Uses a standard, screw-on 9-speed freewheel.
I've heard that Nine Continent N48 hub motors have a variant that can accept 8/9-speed freehub cassetes. So, the newest cassete system, no old screw-on type. That motor also has approx. 1000W of power at 48V at around 22A. It seems it would suit you well, as it is a torque motor for taking care of the hills easily, and yet it has top out speed of about 30 mph on a 26" wheel when running on 48V.
Mabman, e-bikes aren't legally limited to 20 MPH. Rather, once they can go faster than 20 MPH or if they have a motor larger than 750W many states categorize them as mopeds and require them to be licensed and insured. Bikes with gas-powered kits are automatically categorized as mopeds by most states.
Originally Posted by Mabman