Brompton Developments

Sturmey Archer HubThe message from Brompton is one of incremental changes, some small, but others of real importance, or at least, interesting enough to report.Weight is unchanged, as is price, but there have been subtle improvements. To recap briefly, the Brompton has been around since the late 1980s. Although never officially designated as such, early hand-built bike are usually called Mark 1s, the 1991 – 1999 bikes the Mark 2 and more recent machines Mark 3.The post-1999 Mark 3 looked much like its forbears, but was rebuilt almost from scratch, resulting in a lighter, faster and more rugged machine.The only big change since has been from Sturmey Archer 3- or 5-speed hubs to a SRAM 3-speed with the option of a Brompton 2-speed derailleur, giving six gears.

Rear frame

History has come full circle. Five years ago, Sturmey Archer was driven into bankruptcy, later re-emerged as part of the Sunrace group, which is now manufacturing a full range of hubs from a factory in Taiwan.Wary of being tied to SRAM alone, Brompton has redesigned the rear frame of its bikes to accept either type of hub gear. In practice, this means that 3-speed bikes will be equipped with Sturmey Archer hubs, but the 6-speed will continue to use SRAM, because the Sturmey Archer is unable to accommodate the two-speed sprocket assembly used on the 6-speed. Still with us?

These changes raise several questions and answers. If you buy a 3-speed, you will no longer be able to upgrade to a 6-speed without buying a SRAM hub. On the other hand, you can now upgrade to a Sturmey 5-speed hub, should you really want to (there’s a small gear range advantage of the 6-speed). If you have an older bike, with either a Sturmey or SRAM hub, the new rear frame will allow you to fit either hub. Useful for globe-trotters expecting calamity in the Gobi Desert. Incidentally, the new Sturmey 3- speed, like the last Nottingham- built hubs, features ‘ball-locking’ positive engagement – in other words, it should be impossible to wind up in neutral, as occasionally happened when the old hubs where out of adjustment.The Sturmey also has a better reputation for keeping out dirt and grime, so it’s very much a positive step.

Gear selector

Brompton Gear SelectorThe old Sturmey 3-speed shifter was much loved, but has been showing its age (it was designed 70 years ago).The SRAM design is less positive and liable to all sorts of minor niggles, so Brompton designed its own to coincide with the reintroduction of the Sturmey hub, and it will be fitted to all 3-speed bikes.The shifter has a long travel, but to keep it nice and ergonomic there are two levers, one above the other.To change down from 3rd to 2nd, you flick down the lower lever.To change from 2nd to 1st, the upper lever will be in exactly the same place.The lever has to be carefully positioned to work well, but when it does, it’s superb – comfortable and easy to use. Like the rear frame, the new shifter will work with either SRAM or Sturmey hubs, so you can upgrade an older bike if you want.

Rims

Brompton RimsA perennial grumble from high mileage owners is rim wear. Brompton isn’t promising to eradicate the problem, but the new ZX1000 rims are better quality, more precisely machined and including a wear indicator slot – when the slot disappears it’s time to change. Anodised (but not on the wearing faces) the rims certainly look smarter, but we’ll have to wait a few months to discover whether they really are tougher in service.

These changes don’t sound very exciting, but there might be a tiny clue in the following exchange: ‘Is this the 2005 Brompton?’, we asked. ‘No’, they replied. Make of that what you will.

Brompton Bicycle

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