Go Back  Bike Forums > Bike Forums > Folding Bikes
Reload this Page >

Modification of the Brompton

Search
Notices
Folding Bikes Discuss the unique features and issues of folding bikes. Also a great place to learn what folding bike will work best for your needs.

Modification of the Brompton

Thread Tools
 
Search this Thread
 
Old 11-24-04, 10:44 AM
  #1  
Newbie
Thread Starter
 
Join Date: Nov 2004
Posts: 50
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked 0 Times in 0 Posts
Modification of the Brompton

Hi,

I thought you might find this interesting; I found a way to increase the reach of the brompton handle bars to that of a longer bike, using a normal adjustable stem. This mod does no affect the folded size (see photos)

Sam
Samb76 is offline  
Old 11-24-04, 01:08 PM
  #2  
floor sleeper
 
Join Date: Jun 2002
Location: Here and there in the US
Posts: 998

Bikes: Raleigh Twenty, Puch 3 speed road conversion, lookin' into a Karate Monkey for a cruiser

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Any idea if those particular folding type stem dealies are available after-market or seperate of the actual brompton cycle? Did you cut the top of the folding stem off, judging by brompton's website, their folding stems have a clamp on the top...
robertsdvd is offline  
Old 11-24-04, 02:07 PM
  #3  
Life in Mono
 
Join Date: Oct 2004
Location: London
Posts: 498

Bikes: 5 bikes, all the usual types

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3 Times in 2 Posts
That looks good !

I never liked the original Brompton bars - look too much like 'grannies' shopping bike bars. But I thought they had to be that way to clear the end of the front axle ??? is it much wider ? does it improve stiffness ?
Simple Simon is offline  
Old 11-25-04, 11:17 AM
  #4  
Newbie
Thread Starter
 
Join Date: Nov 2004
Posts: 50
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked 0 Times in 0 Posts
A few notes on the modification of the stem;
I cut the original stem using a hacksaw and file about 30mm above the thread which attaches the stem to the fork when folded. A shim was then inserted and a 25.4 zoom adjustable quill stem fitted. These can be bought from a lot of bike shops and are not expensive. The stem will adjust between 90 degrees forward and 90 backward so you can fit and bars you like (including drops). The extra weight on the front wheel slows the bromptons twitchy steering. I fitted a strandard brompton wingnut/bolt to enable adjustment of the stem without tools.

The bars I fitted are a little narrower than the brompton bars, which are deceptively wide, and I've found the narrower bar actually more comfortable. The axle problem is overcome by tilting the stem slightly backward - in practise its not too critical. Stiffness is increased somewhat, although a certain amount comes from the base on the stem (hinge) so cannot be eliminated unless you change the stem altogether.

Hope this answers your questions.
Sam
Samb76 is offline  
Old 01-07-05, 10:40 AM
  #5  
Newbie
Thread Starter
 
Join Date: Nov 2004
Posts: 50
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked 0 Times in 0 Posts
Just in case anyone is interested,

I've been working on bromptons over the christmas period,
and I can offer two custom bromptons:
The spec. includes adjustable handlebars, conversion to 10 speed, lightened cranks, greatly improved brakes. All work is carried out to a very high standard. Because I've sourced used bromptons (both are pristine condition), prices are reasonable.
mail me at imperial_systema@yahoo.com
Samb76 is offline  
Old 01-07-05, 11:37 AM
  #6  
Life in Mono
 
Join Date: Oct 2004
Location: London
Posts: 498

Bikes: 5 bikes, all the usual types

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3 Times in 2 Posts
Pix would be nice !
Simple Simon is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.