Folding Bikes - Modification of the Brompton
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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)
11-24-04, 01:08 PM
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...
11-24-04, 02:07 PM
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 ?
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.
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 firstname.lastname@example.org
01-07-05, 11:37 AM
Pix would be nice !
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