Folding Bikes - Brompton 1-speed and gear inches

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.



PDA

View Full Version : Brompton 1-speed and gear inches

nbnguy98
10-13-08, 04:34 PM
Hi,

Trying to find the gear inches for the Brompton's 1-speed:

1-speed standard?
7% lower gearing?
18% lower gearing?

Thanks!

somnatash
10-13-08, 04:56 PM
Not sure about gear inches but

1-speed standard = 5.93m (probably with sprocket 12t, chainwheel 54t)
hope this helps. I guess for the lower gearings they change the chainwheel for a 50t or 44t (as far as I know there are only 44t, 46t, 50t chain wheels). Of course you can also go and change the sprocket for 13t, 14t or 16t

see also this thread here:
http://yacf.co.uk/forum/index.php?topic=7063.0
makingmark
10-13-08, 09:37 PM
Here you go:
http://www.greenspeed.com.au/brompton/images/option_gearinch_table.gif