4 Speed
4 Speed Kit for Hubsmith Rear Hub - Updated
Updated Apr/2024. Shifter conversion parts are now available for two shifters, (1) Post-2017 left hand 2S shifter, or (2) P/T Line 4S shifter. Please choose the preferred sprocket combination, and according to the shifter you intend to use. Sprocket combinations are abbreviated as follow. 11-13-15-19 -> 1-3-5-9, and 11-13-16-19 -> 1-3-6-9. Color choices, either black, or silver refer to the color of the hub end caps.
4 speed kit for Hubsmith rear hub
With this kit, any Hubsmith rear hub can be upgrade to 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
- Hubsmith rear hub, or private labelled rear hub made by Hubsmith, such as ORZ, MIniMod, H&H, Brombacher, just to name a few.
Other than the factory parts, this package is self contained. No other 3rd party parts are necessary. 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:
- Lockring style 3/4S freehub body, with hub end caps.
- Shifter conversion parts,
- Chain pusher modification parts
- Sprocket set
- Longer tensioner pulley axles for factory pulleys
- 12 speed chain
- Installation instruction & tuning guide
Currently there are two sprocket combinations available, 11-13-15-19, or 11-13-16-19. As well, the hub end caps are available in either black or silver. Please choose accordingly!
If you currently has Hubsmith lockring style 3/4S freehub, that looks like this, then please choose the package w/o freehub.
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.
