Brompton Chains
Replacement chains for your 16 inch wheel Brompton
If you are looking for G Line chains please click here to go to our G Line spares section
Current Brompton folding bikes use two different specs of chains:
- The Brompton A Line / C Line (1-speed, 2-speed, 3-speed or 6-speed) use an 8 speed chain
- The Brompton C Line / P Line / T Line and Electric C Line / P Line / T Line (4-speed / 12-speed) use a 10 speed chain
Which chain do you need?
A: The chain length for a Brompton C line can be worked out based on the number of teeth on the front chain ring and the number of teeth on the largest rear sprocket - as shown in the table below (or watching the video even further down)
| Largest Rear Sprocket | Chain required | Chainring size | Note |
| 12T/13T/14T | QCHAIN096DR | 44T | Reduced gearing 3 speed / single speed |
| 15T/16T | QCHAIN098DR | 44T | Reduced gearing 6 speed |
| 13T | QCHAIN096DR | 46T | Very old original chain ring (probably worn out) |
| 12T/13T/14T | QCHAIN098DR | 50T | Standard 3 speed Brompton |
| 16T | QCHAIN100DR | 50T | Standard 6 speed/Reduced gearing 2 speed |
| 12T/13T/14T | QCHAIN100DR | 54T | Increased gearing 3 speed |
| 15/16T | QCHAIN102DR | 54T | Standard 2 speed/Increased gearing 6 speed |
The Brompton chain for A Line / C Line comes with a PowerLink to make chain removal and installation easy
- We (and Brompton) recommend changing the rear sprocket(s) whenever the chain is changed / replaced (as they tend to wear together, so if you change just the chain, you may well find that the chain slips on the old sprocket when under load)
Brompton bicycles with a 1-speed, 2-speed, 3-speed or 6-speed gear setup use a 3/32 inch 8-speed chain (made for Brompton by SRAM) - Previously these 3/32 inch chains were only used on derailleur (2 and 6 speed) Brompton bikes
A: The P Line / T Line
and since 2023 Brompton Electric P Line - 4-speed / 12-speed
and since 2026 the Brompton C Line / C Line Electric - 4-speed / 12-speed
all come with a choice of the following chains:
- Brompton SL Advance 98 Links
- Brompton SL Advance 100 Links
- Brompton SL Advance 102 Links
- Brompton SL Advance 104 Links
- Brompton SL Advance 106 Links
These are 10 speed chains (the brand used by Brompton is YBN)
Please check the following table for the correct chain lengths:
| Chainring size | Gearing | Chain length |
| 56 | 4-speed / 12-Speed | 106 link |
| 54 | 4-Speed / 12-speed | 104 link |
| 54 and 56 | 1 speed | 102 link |
| 50 | 4-Speed / 12-speed | 102 link |
| 50 | 1 speed | 98 link |
| 44 | 4-speed / 12-speed | 100 link |
We made this short video to show how to:
- Choose the correct chain length / size
- Remove your existing Brompton chain
- Install a new chain on your Brompton