Brompton factory build:
BWR 6-speed
BSR 3-speed
SRAM 6-speed
SRAM 3-speed
SA 3-speed
SA 5-speed
2-speed
Single-speed
Brompton-compatible data only:
Options:
Chainring:
Factory sizes are 54/50/44 teeth (+8%/standard/-12%)
Tyre:
Brompton HP: 16x1 3/8 - ETRTO 37-349
Stelvio: 16x1 1/8 - ETRTO 28-349
Kojak: 16x1 1/4 - ETRTO 32-349
Marathon: 16x1.35 - ETRTO 35-349
Marathon Plus: 16x1.35 - ETRTO 35-349
All Brompton high-pressure tyres
Hub:
BWR (Brompton Wide Range)
BSR (Brompton Standard Range)
SRAM 3-speed
Sturmey Archer 3-speed
Sturmey Archer 5-speed
Sturmey Archer SRF5(w)
Sturmey Archer XRF8(w)
Shimano Nexus 8
Shimano Alfine 8-speed
Shimano Alfine 11-speed
Rohloff Speedhub
Kindernay XIV 14-speed
No internal gears
Schlumpf:
Direct Drive
Mountain-Drive
Speed-Drive
High-Speed-Drive
Units:
Gear Inches
Metres Development
Speed - MPH
Speed - KPH
Gear Inches
Hub Ratios
64%
100%
157%
Rear sprocket-Low:
33.0
51.7
81.0
Rear sprocket-High:
40.6
63.7
99.7
Range: 302%