The Kinetics 8-speed Brompton conversion  uses a Sturmey Archer hub gear with a very wide range - the X-RF8(W) has a 325% gear range. Compared to Brompton’s 6-speed option, it is a wider gear range with only one gear shifter - a low profile twist shifter.  All 8 gears are in sequence, so it’s easier to use than the 6-speed’s  twin-shifter system, and any gear can be selected while stationary. The  smaller front chainset keeps the drivetrain further inside the folded  package. No modification of the frame is needed.

I can fit the 8-speed to an existing  Brompton for you, or I can send you a kit for £300. The kit includes the complete back wheel, chain tensioner, gear shifter and cable, and  replacement chainset. You’ll need a few spanners, and a few allen keys - fitting is not hard, and takes about 30 minutes.

If you want an even wider gear range, the  8-speed combines very well with the Schlumpf Mountain and Speed Drives.

Brompton 8-spd Kit - £300 - delivery takes 2 weeks