Our 8 speed conversion available as a kit (all parts as in above description) with
full fitting instructions and free check-up/fitting (at my workshop) should you need
it. £284.99 inc. U.K p&p ( with either Mk 4 rim or the new twin wall rim)
With Brompton introducing a new wheel rim (2013) this kit is now built to order for
your specific model including building into your Mk2 rim if you wish and supplying
1/8 chain for older models using 1/8 chainrings, please also note older handlebars
of 24mm diameter will (and should be) changed to the 22.2mm, please email me your
requirements , waiting list currently running at 4 weeks.
Special price of £36 to build a matching front wheel if you choose the new Brompton
double wall rim for the kit, simply send me your hub.
Standard Brompton 3/32 chainwheels
Standard 44t, 50t and 54t for service replacement or to tune your current gear set-up,
can also be supplied with the replacement alloy chainguard (please see previous page
for details) pre fitted. U.K. P&p £1.95, overseas customers please email for costs.
Brompton 8 Speed conversion
We can fit the new Sturmey Archer 8 speed hub to your Brompton to give the ease of
8 evenly spaced gears with the simple twist grip gear change.
Suitable for M/P/S/H-type bars and
it retains your Brompton chainwheel
gear ratios are:
With 44t chainwheel 2.30m - 7.50m
With 50t chainwheel 2.65m - 8.60m
With 54t chainwheel 2.85m - 9.25m
Or with lower gear options (details below)
With 40t chainwheel 2.08m - 6.75m
With 39t chainwheel 2.03m - 6.60m
Fitted to your Brompton the cost is £284.99 including new rim, hub and wheel build
using new Sapim spokes, chain tensioner with mods, chain, gear control, grips and
Free Scuff Muffle!.
Lower gearing for all Bromptons (1,2,3,6, 8 and 11 speed)
This is probably the most asked question I get about the Brompton bike, if you have
got the smallest Brompton chainring (44t - standard Brompton chainrings also available
below) and the largest rear sprocket for your model and you still want lower gears
then I can supply (and fit if required) two new options, Stronglight 40t and Alfine
Stronglight 40t chainset, a smaller chainset by the manufacturers of the Brompton
chainrings, the right crank arm is the same style as the current Brompton so you
can either retain your left crank with the Brompton modification to stop the folding
pedal touching the frame or fit the new one supplied with a modification to do the
same. It will use your current bottom bracket cartridge. Supplied with a bespoke
laser cut polished aluminium chainguard £49.99. U.K p&p £1.95 , overseas customers
please email for costs.
Shimano Alfine 39t chainset with chainguard, giving the lowest gear and upgrading
to outboard bottom bracket bearings (included), the left crank arm has been modified
to retain a pedal stop function, £89.99. U.K p&p £1.95, overseas customers please
email for costs.
Nb. not suitable on 11 speed conversion.
Brompton 11 Speed conversion
Fitting the Alfine 11 speed hub to your Brompton requires the widening of the rear
frame (steel), with my jig this is done cold which avoids any paintwork damage, all
the other mods are done to retain a Brompton look, rim options including pre 2013
style and newer double wall rims available, suitable for M/P/S/H- type handlebars
(M/P/H- types need a little adjustment of bars - something many Brompton owners already
do to get a more comfortable brake lever angle - to allow for the bulkier gear shifter
so will increase the width of the folded bike slightly) it retains your Brompton
chainring, gear ratios are:
With 44t chainwheel 1.67m - 6.86m
With 50t chainwheel 1.91m - 7.98m
With 54t chainwheel 2.07m - 8.62m
Or with lower gear options (details below)
With 40t chainwheel 1.52m - 6.38m
Fitted to your Brompton the costs start at £774.99 including new rim, hub and wheel
build using new Sapim spokes, chain tensioner with mods, chain, gear control,Shimano
brake levers, grips and Free Scuff Muffle!
*Of course 11 gears will weigh more than 6 (which gives 302% gear range), to give
an idea the 11 speed wheel inc. hub, spokes, rim and sprocket is 2.5 kgs the Brompton
6 speed wheel inc. hub spokes, rim and sprockets is 1.55 kgs.
* Of course 8 gears will weigh more than 6 (which gives 302% gear range), to give
an idea the 8 speed wheel inc. hub, rim, spokes and sprocket is 2.4 kgs, the Brompton
6 speed wheel inc. hub, rim, spokes and sprockets is 1.55 kgs.
This conversion is currently for steel frames only (new frame can be supplied if
needed), until I try the titanium option in the near future. This will be a to order
package, for fitting at the workshop, please contact me to place a non deposit order
for the next conversion available. Alfine 8 speed conversions also available from
Please note this page has replaced the Bromptons upgrades page of 2011, if you wish
to order the frame clip, saddle, tyres, or pedals pleaseclick here and for a current
list of Brompton bikes for sale click here.
Well if Brompton can have a Project X with their e.brompton project why can’t I,
it’s not an electric version which sadly has given Brompton headaches for many years,
but another gear system that could give a 500%!! gear range for a very reasonable
cost, it’s all hush-hush so please don’t ask... If it works you will be the first
to know via this page...
...update..........it was looking good but I now know I will have to make a completely
new chain tensioner, so until I get my CNC milling machine this conversion is on