Brammo Owners Forum

General => Off Topic => Topic started by: Richard230 on May 14, 2012, 05:00:18 PM

Title: Audi builds an electric bicycle
Post by: Richard230 on May 14, 2012, 05:00:18 PM

Audi has developed a powerful (for an e-bike) prototype electric bicycle, complete with a 9-speed transmission and a torque rating that seems to be a misprint.  Read about it here:

http://www.visordown.com/motorcycle-news--general-news/could-audis-e-bike-become-a-ducati/20646.html (http://www.visordown.com/motorcycle-news--general-news/could-audis-e-bike-become-a-ducati/20646.html)

Title: Re: Audi builds an electric bicycle
Post by: 860 on May 14, 2012, 05:23:43 PM

Quote from: Richard230 on May 14, 2012, 05:00:18 PM

Audi has developed a powerful (for an e-bike) prototype electric bicycle, complete with a 9-speed transmission and a torque rating that seems to be a misprint.  Read about it here:

http://www.visordown.com/motorcycle-news--general-news/could-audis-e-bike-become-a-ducati/20646.html (http://www.visordown.com/motorcycle-news--general-news/could-audis-e-bike-become-a-ducati/20646.html)

"184lb/ft of torque at the rear wheel." 

I'm guessing that is the torque after gearing.  60lb/ft of torque at the motor with a 3:1 gearing ratio would be 180lb/ft.  So would 30lb/ft with a 6:1 gear ratio, etc.

Title: Re: Audi builds an electric bicycle
Post by: Richard230 on May 14, 2012, 07:36:46 PM

That makes sense. I was thinking of the IC motorcycle dyno tests which seem to provide torque as measured in high gear only. I guess if they measured torque in first gear, it would be a much larger number.

Title: Re: Audi builds an electric bicycle
Post by: Shinysideup on May 14, 2012, 08:53:46 PM

Yeah I have an electric bicycle where hub motor drives through a 14-speed rear hub. It'll haul 400 lbs up a 30 degree hill. Slowly.