Tern Vektron first ride review

Can this folding e-bike kill two birds with one stone?

GBP £3,000.00 RRP | USD $3,400.00
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Folding bikes have long been popular with commuters, city dwellers and everyone else short on space. E-bikes give folk a bit of help up the hills. So can the new Tern Vektron satisfy both target markets?


We’ve given it a good riding around the hilly, cobbled, mucky streets of Bristol and here are our thoughts.

Tern Vektron spec overview

  • Frame: Alloy with Quadric dropouts
  • Fork: Tern Tarsus
  • Shift levers: Shimano Deore
  • Brakes: Shimano Deore hydraulic disc brakes
  • Crankset: FSA for Bosch (1x10t)
  • Cassette: Shimano Deore (11-34t, 10spd)
  • Rear derailleur: Shimano Deore
  • Electronic drive unit: Bosch Active 250W
  • Wheels/tyres: Kinetix Comp 20in wheels / Schwalbe Big Apple tyres (2.15in)
  • Saddle: Tern Porter+
  • Handlebar: Tern Physis handlepost / Andros adjustable stem
  • Weight: 21.76kg / 47.97lbs

Tern Vektron frame and equipment

The hinge at the centre of the Vektron frame is easy to operate and its safety catch is reassuring to see
Oli Woodman / Immediate Media

Portability is achieved through a three-step fold that will be familiar to anyone who’s used a Tern before.

A hinge in the centre section comes first, in this case the heavy-duty OCL+ frame joint first seen on Tern’s Node cargo bike.

A quick-release clasp below the stem folds down the handlebars, then all that’s left is to remove the pedals and you’re done.

Tern says that the Vektron will fit under a desk. But they haven’t encountered the desks at the BikeRadar office…
Oli Woodman / Immediate Media

The ready-to-stash package isn’t as small as a folded Brompton — but then it can’t be, with 20in wheels (rather than the Brompton’s 16in), and all that electro-wizardry crammed in, plus the ruggedisation that the latter requires.

Tern says it will go into a car boot or underneath a desk, and we reckon that most people will probably manage this. Good luck carrying it up flights of stairs though. At 21kg (48lbs), this is one heavy beast, though it can be wheeled in its semi-folded state to make things easier.

Bosch Active line motor will provide assistance up to 25km/h or more for regions that allow it
Oli Woodman / Immediate Media

The equipment is all solid stuff: a Bosch Active Drive 250W motor and 300Wh PowerPack battery, Bosch Purion e-bike display, Shimano Deore 10-speed drivetrain and hydraulic disc brakes are all excellent performers.

The Schwalbe Big Apple tyres are large, but they do a good job of taming Bristol’s cobbles. 

The clever handlebar adjustment system allows for tool-free reach and angle adjustment
Oli Woodman / Immediate Media

The finishing kit is all good too. Tern’s Andros adjustable stem lets riders change the height and reach within a range of around 8cm (3in) without tools, to customise fit.

Coupled with the telescopic seatpost, this means that the Vektron can be shared by the whole family and fit a huge range of rider heights: from 147–195cm / 4’10”–6’5”.

The Tern Porter+ saddle is comfy too, with gel cushioning on top and a moulded rubber grip underneath to make carrying more comfortable.

The cargo rack adds useful haul-ability to an already practical machine
Oli Woodman / Immediate Media

There are plenty of practical little extras for the city-going cyclist, like a rugged kickstand, extensive chainguard, magnetic clasps on the fork and rear triangle for keeping the Vektron folded securely, a rear pannier rack with integrated bungee straps, fixings on the head tube for a front rack, full mudguards and powerful front and rear lights driven by the Bosch PowerPack battery.

A walk-assist function is also supported.

Tern Vektron ride impressions

The Vektron is a lot of fun to ride and made us rethink what’s possible on a folding bike
Oli Woodman / Immediate Media

The Vektron may have unusual looks, but once you’re in the saddle and moving, it’s a pleasant and reassuringly normal bike to ride.

During my varied test loop, the fat tyres, rugged frame and heavy weight helped to absorb big bumps and imperfect tarmac, and the Ergon GP10 grips were kind on my hands.

But you’ll need that electronic assist if you’re going to enjoy the ride.

There are four power modes available (Turbo, Sport, Tour and Eco), with Tern claiming a range of up to 100km (62miles) on Eco mode from a complete charge.

We ran our test unit from a full charge, mostly on Turbo mode, and after nearly three hours we still had more than half the battery left.

The mid-mounted Bosch motor is smooth in the way it delivers power, with three sensors taking over a thousand measurements a second to ensure that there’s no nasty jolting sensation.

Being a pedelec, it will only deliver power when you’re actually turning the pedals, up to a maximum speed of 25kph (or 32kph in the US). 

Mounted at the left-hand side of the handlebar, Bosch’s Purion display unit can cycle through four levels of power assistance via two large buttons
Oli Woodman / Immediate Media

I tried riding up a hill in Turbo mode then switching down a power mode (Turbo>Sport>Tour>Eco>Off) every few seconds, and the difference was remarkable.

Once I’d reached Eco mode, the assistance was virtually unnoticeable, and when I switched it off completely it was like riding uphill through thick mud.

I quickly tapped the Purion display to power up Turbo mode again (don’t judge me).

Don’t forget to keep it charged and the Tern Vektron will quietly conquer any urban challenge.

The mountain bike-derived 1×10 drivetrain seems like a solid choice to us
Oli Woodman / Immediate Media

The Shimano Deore drivetrain provided ample gear range for my test loop, though inevitably the 11-34t cassette means that jumps between cogs are quite big, at two teeth per cog at minimum.

The hydraulic Deore disc brakes are equally good, with plenty of stopping power and control when needed.

The rain absolutely hammered down during the first half of my test ride and braking performance remained impressive.

How about the fold? Well I managed to get it down to a respectable 20 seconds: not as slick and swift as my Brompton, but still easily good enough for a commute.

I do think that you’d struggle to fit the folded package into the cramped rush-hour train that I normally take — I admit that I didn’t try, simply because I don’t hate myself or my fellow commuters enough to try. But it’ll go into an apartment or office easily enough, I think.

Tern Vektron price and availability

The Tern Vektron is priced at £3,000 / €3,000 / $3,400, and will be available in all three markets by the end of February 2017.

Australian pricing and availability are yet to be confirmed.

Tern Vektron vs. the competition

The Brompton delivers a best-in-class fold, but a factory-made electric version isn’t ready quite yet
Oli Woodman / Immediate Media

As already mentioned, the Brompton is a hugely popular folding bike — but the UK firm doesn’t make its own motorised version… yet.

Several companies out there will sell you an electrified version of the Brompton, such as the Nano 2 from UK company Nano Electric Bikes, available as a kit (from £710) or on a complete new Brompton (from £1,900). It offers a claimed range of up to 40 miles and adds just 4kg to a Brompton.

Brompton itself has said that it plans to launch a motorised version of its folding bike by the end of 2017 and has invested millions of pounds in a new facility in west London in order to produce the new machine, in partnership with F1 group Williams.

Brompton’s chief sales and marketing officer, Stephen Loftus, told BikeRadar last year that the new Brompton will be based on the existing design, rather than a complete overhaul.

The BH EasyGo Volt has a slightly smaller claimed range than the Tern Vektron and comes in a lot cheaper and lighter

Another possibility is the BH EasyGo Volt, powered from the rear hub by a 250W motor and Samsung 250Wh battery, with a smaller claimed range of up to 50km (28 miles), and a lighter weight at 17.2kg (38lbs).

The price is lighter too, at £1,599 / $1,499 / AU$ TBC.

Finally, the Gocycle G3 is a futuristic-looking collapsible bike, that boasts a claimed range of 80km (50 miles) and a significantly lighter overall weight at 16.3kg (36lbs).

It is more expensive though, retailing at £3,299, and its makers say it’s not really a folding bike — it can be made stowable, but is not a bicycle that you should fold up on a station platform or when you arrive at work.

Tern Vektron early verdict

As a folding bike, I think the Tern Vektron is too big and too heavy to impress jaded commuters.

But in combination with a Bosch motor, rugged ride and full complement of practical accessories, it becomes a much more attractive machine.


My afternoon test ride with it was a hell of a lot of fun and with solid load-carrying capabilities, it could become a solid town runaround and groceries wagon.

Product Specifications


Name Vektron
Brand Tern

Available Colours Black
Rear Derailleur Shimano Deore Shadow
Weight (lb) 48
Year 2017
Weight (kg) 21
Stem Tern Andros
Shifters Shimano Deore, 1x10 spd
Seatpost Tern Telescopic,
Saddle Tern Porter+
Rims Kinetix Comp, for disc
Rear Tyre Size 20x1.5
Rear Tyre Schwalbe Big Apple
Rear Hub Shimano disc
Pedals LiteForm QR
Bottom Bracket Bosch
Handlebar Tern Physis
Grips/Tape Ergon GP10
Front Tyre Size 20x1.5
Front Tyre Schwalbe Big Apple
Front Hub Shimano disc
Frame Material Alloy
Fork Tern Tarsus
Cranks FSA for Bosch, 1x10t
Chain 10 spd, DHT for eBike, GST corrosion resistant coating
Cassette Shimano 11-34T, 10 spd
Brakes Shimano Deore hydraulic disc
Brake Levers Shimano Deore