Cyclist
Now even Brompton has gone 12-speed
Folding bike giant Brompton has launched a 12-speed gearing option on a number of its lines.
The London-based company’s internationally popular range was previously limited to 2-speed, 3-speed, 4-speed and 6-speed gearing, and this development builds upon its existing technology to ensure that it has little negative impact on the established design – and folding – of a Brompton bike.
The 12-gear system has been implemented using a 4-speed cassette and rear derailleur, which was originally designed and produced for the lightweight T Line and which Brompton says weighs just 60g, alongside a 3-speed Sturmey-Archer hub gear, which sits inside the hub of the rear wheel. In combination with the cassette, the hub acts as a front derailleur and triple chainset would, but its design means the bike’s fold isn’t affected and is easier to maintain, while allowing the four gears to become 12.
The ‘Explore’ models of the P Line, T Line, Electric P Line and Electric C Line are those that are now available with 12-speed gearing, with claimed weights ranging from 8.8kg on the T Line Explore to 17.3kg on the Electric C Line Explore and prices ranging from £2,450 on the P Line Explore to £4,725 on the T Line Explore.
Alongside this update Brompton has given the P Line and Electric P Line the Quick Release pedals (as opposed to folding pedal) previously seen just on the T Line, and the Electric C Line now has the same rear frame as the P Line, which is easier to fold/unfold and has better ‘rollability’. There are also three new colours for both the C and P lines.
Why has Brompton developed 12-speed gearing?
‘It’s something that we noticed in market feedback, especially in hilly cities, we found out in focus groups in cities like Seattle, San Francisco and Shanghai that people use the bike to ride longer distances and steeper inclines, so there was a need for more gears,’ says Brompton’s senior product manager Rafa Nascimento. ‘Their main ask for “a more capable, just as compact” Brompton.’
Senior design engineer Shaun Pirie explains that the 12 gears should be seen in three sets of four – as the hub gearing suggests – with the middle hub gear what most riders will be using most of the time, acting almost identically to a 4-speed Brompton, switching to the first hub gear for hills and going up to the third hub gear mostly for downhills to prevent spinning out.
It’s those top gears where Brompton sees the benefit for e-bike users too. ‘We found that more than 70% of electric users were asking for more gears, and lower-end folding bikes start with seven gears so there was a competitive aspect too,’ says Nascimento. ‘I think the main benefit is to keep cadence after the motor cuts off [due to speed restrictions], I’m an electric rider and I notice the difference every day how quickly the motor cuts off.’
Pirie says the 12-speed models mean buyers will have a clearer choice whether they want to prioritise light weight for carrying (fewer gears) or functionality for harder riding (more gears).
How much range does it actually provide?
Nascimento has provided this handy graph to show the increase in capacity going up to 12-speed has and how it compares to the gearing that road bikes offer.
The external gears on the bike are a 50-tooth chainring and an 11-18t cassette (with 13t and 15t sprockets in the middle of the block) and the three hub gear ratios are 0.638, 1 and 1.567. That means the lowest hub gear is just over half of the middle and the top gear is just over 1.5× the middle gears. The graph shows the results of this really well, as it means there is very little crossover between gears when moving up and down the hub gears, unlike a road bike, so it’s a lot closer to genuinely having 12 gears than a 2×12 road bike is to having 24.
In practice that has the potential to be quite fiddly at first because to change down the hub you’ll likely then want to move up the cassette – and vice versa – but the shifting is fairly straightforward with the right shifter controlling the hub gear and the left the cassette.
Brompton 12-speed bikes, prices and weighs
Brompton T Line Explore 12-speed
Weight: From 8.8kg (claimed)
Price: £4,725
Brompton P Line Explore 12-speed
Weight: From 10.5kg (claimed)
Price: £2,450
Brompton Electric P Line Explore 12-speed
Weight: From 16.3kg (claimed)
Price: £3,895
Brompton Electric C Line Explore 12-speed
Weight: From 17.3kg (claimed)
Price: £3,150
For more information or to buy one, visit brompton.com
Keep your eyes peeled for our full review of the Brompton P Line Explore 12-speed
The post Now even Brompton has gone 12-speed appeared first on Cyclist.