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Brompton’s electric P line is its lightest-ever folding e-bike – but how does it handle?

The power-assisted, British-built bike is the ideal alternative to busy commuter trains and sweaty backs

The bike is available in black and grey, with and without the luggage rack

Brompton has launched its lightest-ever folding electric bike. The new electric P line weighs 12.7kg without its battery, which is roughly 3kg lighter than Brompton’s existing electric C line bike.

While folding electric bikes are already a common sight whizzing along our cycle paths, the iconic British manufacturer has taken a more considered approach to developing electrified versions of its most popular bike ranges.

That means Brompton has gone to great lengths to preserve the bike’s distinctive silhouette and ensure its 20-second folding technique remains unchanged by the addition of an electric motor and battery.

The result is a new motor-assisted version of its performance-leaning P line bike, a lighter ride with a four-speed gear system, and a custom-built derailleur designed to fit tightly into the bike’s folded-up form. Bigger roller wheels, a titanium-and-steel frame, an optional roller rack and a locking seat post all combine to make an electric bike that’s way easier to move around than the original electric Brompton.

To find out how it performs on the road, we’ve been zooming around on the new electric P line for the past few weeks. Here’s what we thought of Brompton’s latest ride.

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How we tested

We’ve been pootling around London town on the Brompton electric P line for a few weeks leading up and after to the folding bike’s announcement and launch. We commuted across the city along a cycle superhighway, on a route that includes a steep incline that brings all but the most steely-calved Santander cyclists to their knees. We also took the bike out for leisurely rides around the park, as well as to venues where storing a bike could have caused problems.

Our tester lives in a small flat in a high-rise, giving them ample opportunity to test the bike’s portability and storability.

Brompton electric P line: From £3,695, Brompton.com

The battery detaches with a button press and comes with a shoulder strap

  • Range: Up to 70km
  • Charging time: Four hours (two with optional Brompton charger)
  • Folded size: 64.5cm x 56.5cm x 27cm
  • Weight: 15.6kg (15.9kg with optional roller rack)
  • Frame materials: Steel and titanium
  • Drivetrain: Four-speed

The Brompton’s party trick is folding down to something about the size of a suitcase. With a click of a switch, a few twiddles of a thingy, and a quick flick of the wrist, the entire frame seems to collapse in on itself in a way that defies the laws of nature.

It’s far from the only folding bike on the market, but no other bike we’ve tested folds up quite like a Brompton. Most bikes, when folded, have some odd part jutting out and ready to snag a trouser leg or gouge a dent in your unsuspected shin. The Brompton is meticulously engineered to fit tidily into an imaginary bounding box.

The bike feels evenly balanced when folded, too – something many other bikes get wrong – so that it doesn’t veer to one side or move in an unexpected way when it’s rolled along by its seat post. You can perch it on the step of an escalator and not feel like you’re about to cause some terrible accident.

Like all e-bikes, the Brompton electric P line assists up to 15.5mph

This portability is what sets this Brompton apart from other bikes, so it’s no surprise that when electrifying the performance-focused P line, the designers took every step to ensure it stayed that way. The battery pack snaps into the front luggage slot, and comes with a shoulder strap for easy carrying. The 250W motor is enclosed within the front wheel hub and doesn’t interfere with the basic shape and silhouette of the bike.

You’d have to know what you were looking for to tell it was electric, though other riders might suspect you’ve got some help when you zip away from the lights, propelled by some unseen ghostly force. The electric P line uses a slightly different set of sensors to the brand’s existing electric bike (the more affordable electric C line), which gives it noticeably more even power delivery.

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This makes it smoother and more comfortable to ride, particularly if your commute involves lots of starting and stopping. Whereas the electric C line could be felt “kicking in” once you began pedalling, the electric P line accelerates far more politely. The electric assistance also backs off a little as it approaches the e-bike’s 15.5mph speed limit. This avoids a curious and unpleasant sensation you get on some e-bikes: the feeling that you’d just ridden into a puddle of treacle as the law-abiding motor cuts out and your legs suddenly pick up the slack.

Brompton’s reduced the number of gears on the electric P line to just four, which is plenty for an e-bike. Dropping to a lower gear with the single shifter comes in handy if your office bike parking is at the bottom of a steep ramp, when coming off a canal towpath, or just when tackling big hills. Throughout, the electric P line is incredibly well built and finished, from the custom derailleur to the sleek, lightweight saddle.

Take it to the park, take it to the loo-roll section of Waitrose, take it wherever you like

The electric P line Brompton is naturally front-heavy, thanks to that big loaf of a battery hovering above the front wheel, meaning the steering can feel jittery at first. This can take some getting used to if you’re trading down from a full-size bike or one with a mid-mounted motor, but you soon get a feel for it. The option to choose from a mid-height or high handlebar also gives you a choice of riding styles too, so you can customise the bike around whatever feels most comfortable.

The electric P line even handles well when you’re not actually riding it. The new seat post can be locked in place halfway down, which when coupled with the optional roller frame lets you pull or push the bike around like a piece of luggage. The electric P line is a bike you can hop on and take for a ride without ever having to think about where you’ll park it (it fits under a desk), whether a cloakroom will accept it (we’re yet to find one that won’t), and how you’ll get it home (folding bikes are welcome on all trains, trams and tube lines).

The Brompton can be folded away in under 20 seconds

Even though this is the lightest-ever electric Brompton, it’s not something you’ll easily forget you’re carrying around – 12.7kg of titanium and steel is still a lot to haul up a few flights of stairs – but crucially the bike doesn’t feel bulky when carried. When picked up and held by the saddle, the centre of gravity keeps the folded bike out of the way of your legs and clothing as you walk. That might sound obvious, but it’s a small detail so many other folders get completely wrong (we have the bruises to prove it).

The verdict: Brompton electric P line

There really isn’t much to fault with the electric P line, besides the name sounding a bit like a PSA about not weeing over the edge of train platforms. Besides that small point, we can say that the lightest electric bike Brompton makes is also its best.

This Brompton is a premium and lightweight folding bike, designed around the practical reality of living, working and playing in the big city. A true upgrade from the electric C line, it’s worth every extra penny.

Brompton electric P line

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