4 Speed
3 to 4 Speed Upgrade Kit
3 to 4 speed upgrade kit
If you already have a 3 speed set up that has room on the freehub for 1 more sprocket, then this kit is for you.
This kit will include the 4 speed compatible shifter internal and chain pusher parts, together with an additional sprocket and spacer. Tensioner pulley axles, as well as a uncut chain are also included.
Updated Apr/2024:
There are now two choices for the left hand shifter conversion parts. Please refer to their respective pages for further details.
Post-2017 2 speed shifter,
P/T Line 4 speed shifter.
Prerequisites:
- Brompton post 2017 LH 2 speed shifter OR P/T Line 4 speed shifter
- Brompton Chain Pusher
- Brompton Spring Mechanism
- Any rear hub with lockring style freehub body and can accmmodate 4 or more sprockets.
If you are not using Brompton factory chain tensioner or aftermarket chain tensioners making use of factory pulleys, please contact the tensioner maker on whether the pulley axles can be extended.
Package Content:
- Shifter conversion parts,
- Chain pusher modification parts
- 18T or 19T Sprocket/spacer (Please choose) set
- Longer tensioner pulley axles for factory pulleys
- 12 speed chain
- Installation instructions for chain pusher & shifter parts
