Building an electric moped

Prozac-on-Toast

Just Joined
Jul 11, 2007
1
0
Hi,

I want to build an electric moped with the styling of an old moped like the Honda C90 to commute to work on. My plan is to do the following:

- Acquire an old bicycle with at least 5 gears.
- Modify the pedal drive to be fixed in a gear at which it can be moved, with enough effort, at a reasonable speed using the pedals.
- Set up a chain and shifter mechanism to link the other gears directly to an electric motor.
- Install batteries and controller. Paint, install lights and maybe some fairings.

I do realise it may be heavier and slightly more powerful than is technically allowed by law, but never mind.

My main question relates to the drivetrain. Are gears really required on an E-bike? What kind of setup do those of you who have built your own use?

Any help would be appreciated - when I get started with this I'll be sure to post a build log on here!
 

Baboonking

Pedelecer
Nov 4, 2006
147
6
Watford
Hi and welcome. Sounds like an interesting project.

I have a 30mph 1500 watt peak ebike/electric moped but I just modified the a standard electric bike kit to get the extra power.

I imagine the drive train will be the trickiest part. You get fit dual freewheel sprockets for bikes but they're usually pricey. Some people use a single chain for the motor and pedals.

There a few examples below if you can wade though all the other EV's:D

EV Photo Album: Our Electric Cars on the Web

Are gears really required on an E-bike? What kind of setup do those of you who have built your own use?
Not required. Most ebikes and electric scooters are fixed gear. There is a performance and efficiency penalty though.


Just out of curiousity why not just convert a honda 90 to electric directly, I imagine it would be safer at 30 plus mph?