4 Speed
4 Speed Kit without Freehub
Sprocket combinations are abbreviated as follow. 11-13-15-19 -> 1-3-5-9, and 11-13-16-19 -> 1-3-6-9. Please choose according to the sprocket combiantion, and the shifter you intend to use.
4 speed kit without freehub
If you already have a rear hub tha can accommodate 4 sprockets, then this is the kit for you. This kit will offer 4 speed with 11T-19T (173%) gear range. The kit basically bring the gear range/ratio to the same level as the 4 speed P/T line.
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
- Sprocket set
- Longer tensioner pulley axles for factory pulleys
- 12 speed chain
- Installation instruction
Currently there are two sprocket combinations available, either 11-13-15-19, or 11-13-16-19. Please choose accordingly!
Notes:
- After installing the new freehub, the rear wheel will need to be re-dished. Wheel re-dishing is best done by professional with equipment/tools and expereinces. Wheel re-dishing in most cases, will not require changing the spokes.
- When using 11T as the smallest sprocket, the plastic protrusion on the back side of the chain tensioner will need to be removed, as it can interfere with the chain path.
- Older Hubsmith rear hubs may come with shorter axle (148mm), and in such case, axle extension nut will be required.
