
Keep Your Brompton Drivetrain Running Smooth
This 50-tooth chainring and guard assembly is the factory-style replacement for Brompton bikes equipped with the spider-type crankset. It restores crisp power transfer and clean chainline while shielding your trouser cuffs and keeping the chain where it belongs.
Matched to Brompton’s standard gearing, it’s ideal when your original ring is worn, bent, or you’re returning a bike to stock after gearing changes. The integrated guard keeps things tidy without adding fussy extra parts.
Design That Works
- Authentic Brompton replacement for spider-type cranksets (2013 and later).
- 50T size matches the stock gearing on many 3- and 6-speed Brompton models.
- Integrated chain guard helps protect clothing and reduces chain derailment.
- Direct fit on Brompton spider crank arms with no adapters required.
- Durable alloy construction with a clean silver finish that suits any frame color.
- Can be used to replace other spider chainring sizes (44T or 54T) when paired with the correct chain length.