September 17th, 2008
Brompton 6-Speed Wide Range Hub
Brompton is now offering a wide-range 6-speed internal gear hub as an option on all their models. Manufactured by Sturmey Archer, it will replace their current SRAM 6-speed hub. The new BWR, as they’re calling it, would make a nice upgrade for those who are currently running the S-A 3-speed or the SRAM 6-speed (which has a narrower range).
From the Brompton press release:
The new configuration for 6-speed Bromptons will feature a wide-range hub of our design, manufactured by Sturmey Archer; the present 6-speed arrangement, employing a SRAM hub, will be discontinued from 1 January 2009. We believe that the Brompton Wide Range Hub [BWR], together with Brompton’s derailleur system, sets a new standard in folding bike gearing systems. It offers:
- An evenly-stepped gear range (302%) that is comparable to the leading 8-speed hubs; but
- It uses only a single epicyclic gear train (instead of three), thereby maximising efficiency;
- At 0.94kg, it weighs almost half as much as other hub gears;
- It comes in the same small package as the current three-speed hub, allowing existing owners to upgrade easily; and
- It is typically-Brompton: robust and built to last… owners can expect the same reliability as with the classic three-speed hub.
We will be supplying a 16-tooth and a 13-tooth sprocket with the BWR which, with a 50-tooth chain wheel, will give the following distances of travel:
Gear 1: 33.0 gear inches (2.63 metres along the ground)
Gear 2: 40.5 gear inches (3.23 metres travel)
Gear 3: 51.5 gear inches (4.11 metres travel)
Gear 4: 63.5 gear inches (5.06 metres travel)
Gear 5: 81.0 gear inches (6.45 metres travel)
Gear 6: 99.5 gear inches (7.94 metres travel)
This represents a gear range (top gear/bottom gear) of 302%; by comparison, the current SRAM 6-speed arrangement offers a range of 215%. Like our existing 6-speed offering, however, the gearing may be raised or lowered by fitting a 54-tooth (+8%) or 44-tooth (-12%) chain wheel in place of the standard.
[via VeloVision]
5 Responses to “Brompton 6-Speed Wide Range Hub”
I wonder if SA will have this available or if it will be a Brompton-only thing. Since I’m about to move back to the hilly East Bay it might be nice to upgrade my three speed to something with a little more spread.
The flip side of this is that it seems they will no longer offer the current six-speed setup with the nice 15% steps between gears. So if you want smaller steps than 25%, you can’t have it.
That bothers me a little because currently there are two after-market options to turn the six speeds into twelve, namely the schlumpf drive and Steve Parry’s derailleur clamp with lets you mount a second chainwheel. So right now you can have both tightly spaced gears and wide range; if Brompton goes through with the plans you will only be able to get wide range, not tightly spaced gears.
I have the current six-speed and like it. Which means I’m not really in the market for a new Brompton… though a titanium 2-speed wouldn’t be hard to find a space for… hmm…
I think this new hub is great news! My friend has a Brommie with a Schlumpf and uses it for loaded touring. Great, but an expensive after market fix.
Ideally, I’d like to get the low end into the 20s (gear inches) and this looks like it might work.
there is too much spread here. i need something like: 73, 65, 55,45 all in a row. is there a way to get those ratios with the new hub? thanks b
Bill,
The old SRAM hub had a tighter spread of 215%. You should still be able to get the old hub for a while since most of the current inventory in shops is from this year or last.
Alan
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