Brompton wheels & drivetrain specialist

This is a small but complete package to upgrade the P/T line gearing from 4 to 5 speed. It is a great simple kit for P/T line owners who want an extra gear for the hills.
 
This conversion process makes use of existing equipment as much as possible, and only involves changing the sprockets, the shifter internal part, and the chain.
 
While we do make the shifter conversion parts available by itself, the kit includes sprockets that have been tested to work, taking the uncertainty out of the conversion process.
 
In this kit, the factory sprockets and spacers are replaced by thinner ones, not be adding one more. It is not possible or unsafe to add one more sprocket, while keeping the existing ones, due to the lack of physical space. The new thinner sprockets and spacer supplied in this package will fit the factory rear hub without the dust cover.

The factory shifter after the conversion will operate 5 sprockets in the new sprocket spacing. The shifter parts are available in two versions. V1 is can only be use with factory derailleur, while V2 is compatible with both factory derailleur and 3rd party derailleurs. The 3rd party derailleurs must have the same cable pulls as the Brompton factory derailleurs.

Due to the thinner sprockets and spacing, a narrower chain is supplied. The conversion process is non-destructive and completely reversible.
 
Pre-requisites:
P/T Line 4 speed shifter
P/T Line Advanced Derailleur and compatible tensioner.
P/T Line rear wheel, or aftermarket wheel compatible with 5 11s sprockets.
 
Kit Content:
- 4 to 5 speed shifter conversion parts
- 11-13-15-18-21T sprockets and spacers, in either silver or black.
- 12 speed chain, in either silver or black.
 
Please select the the color of the sprocket/chain, as well as the version of the shifter parts, either V1, or V2, and then click on the "Add to cart" text.
 
Instruction will be provided in the form of Youtube video