Lightweight & Ultra Wide Gear Range / No more walking brommie up the hill
Lighter than stock Single Speed Chainring yet with duo-chainring sizes for wide gear range.
Unique Pattern and Robust Rigidity.
7075 Aero Spec Aluminum with T6 heat treatment, lightwight yet ultra strong and durable
Black, Silver Standard Colours
Stock BB compatible, spacer included to correct chainline.
Weight : 124g
Made in Taiwan
5 teeth on 33T chainring are missing (picture below) to accommodate the chainring bolts. Not affecting Chain loading and durability.
Try not to use the 33T chainring with the smallest cog. A slant chainline may cause the chain to rub against big chainring. It is a good practice to use the small 33T chainring with biggest cog to form a straight chainlne and also the smallest gear inches (lowest gearing) for most easy climbing.
BCD130 Brompton stock crankset spec, also includes spacer for rear frame clearance.
No derailleur or thumb shifter included, you can source your own. We recommend for simplicity and weight saving, just use your foot or sticks to shift gear.
Remove chainring and crank arms.
Replace old chainring with duo-chainring, washers included on bolts.
Take out left Bottom Bracket Cap.
Put in spacer on the right side of the BB axle (Chainring side), fasten the caps.
This should give right side small chainring enough clearance to Brompton rear frame.
Half fold the rear frame and check if the chain touching frame stay. Play with the fold and unfold to make sure all is clear. Spacer included (3mm) should give enough clearance. But Brompton production tolerance might differ between bikes, let us know if more spacer is required.
Replace Duo Chainring and crank arms. Tighten them.