Specialized Turbo Tero X 4.0 review: The new Turbo Tero X e-bike line-up deals effortlessly with singletrack terrain, and looks to have mass appeal…

Specialized Turbo Tero X 4.0

$4,500 / £3,750, specialized.com


  • Good handling for a heavy bike.
  • Long range even on full power.
  • Can carry cargo up to 90kg.


  • Expensive for a utility bike.

Weight: 4/5
Power: 4.5/5
Range: 4.5/5
OVERALL: 4.5/5

The latest range of full-suspension e-bikes from Specialized may look like an all-mountain trail tamer but it also has more utilitarian ambitions. The Specialized Turbo Tero X is well equipped with fat tyres and full suspension, but rigid fenders and cargo carrying capabilities mean it’s just at home on camping trips and urban exploits as it is in the local woods or trail centre. See how it stacks up against the other best electric bikes.

A man riding the Specialized Turbo Tero X on a woodland trail
The Tero X’s full-suspension design helps flatten out rough woodland trails

Specialized Turbo Tero X range

So Specialized markets its three versions of the Tero X as an SUV as much as an MTB. But can it deliver on both fronts, or is it a compromise between the two? This Tero X 4.0 is the lowest in the range – there’s a 5.0 at £5,000 and a 6.0 at £6,000 – but it’s by no means low on spec.

The first thing you’ll notice looking at the bike side-on is the wheels are different sizes. A bit like a motorcross bike, the Specialized Turbo Tero X has a slightly smaller rear wheel than the front. It’s a 27.5-inch wheel compared to a 29er. The reason for this offset design is to put the rider ‘in’ the bike, rather than ‘on’ it. It does make a difference and helps you feel in control manoeuvering in tight traffic. The only variation is the small frame size, which has 27.5-inch wheels front and rear to stop the cockpit feeling too tall.

Another design feature aimed to inspire confidence in traffic is the Tero X’s dropper post. Most mountain bikes have dropper posts to lower the rider’s centre of gravity during technical descents. The thinking behind it here is to allow you to sink a little as you stop, making it easier to put your feet down flat rather than on tiptoes.

Both design features really do make you feel more nimble and in control on what is a hefty machine. Specialized recognises the Tero X’s substantial weight (26.7kg / 58.9lb) and has incorporated a handy rider-assist button, for when you need to get off and push.

Overhead view of the Specialized Turbo Tero X handlebars and control centre
The Tero X’s MasterMind control panel is well lit and easy to read

Specialized Turbo Tero X control

Speaking of control, the 250W Turbo Operating System gives you three power modes – Eco, Trail and Turbo – at the flick of a switch. In constant Turbo mode one charge of the battery will give you at least a 70km (44 mile) range, but you can expect much more if you manage the power output. That’s with the 530Wh battery found in the Tero X 4.0.

You can go even further between charges with the 5.0 and 6.0, as both have a larger 710Wh battery. All the batteries are all removeable for easy charging at home or the office. Specialized maintains the battery will still hold 75% of its power after two years or 300 cycles – by which time you could have ridden up to 21,000km (13,000 miles).

There’s a micro-shift mode too, that allows you to nudge power up or down by 10%. Syncing the MasterMind control panel to the Mission Control app gives you access to with this and other range optimization tools, as well as advanced tuning features, on-ride diagnostics and system updates.

The MasterMind unit also has ANT+ and Bluetooth connectivity, a customisable screen and a display made from Gorilla Glass which should withstand knocks and scratches. The rider coaching feature accessible here is particularly useful, with a coloured bar guiding you into higher or lower rev ranges for optimal cycling efficiency.

Out on the trail, the ride is quite a revelation. Although this beefy machines isn’t the fastest starter, a quick blast of  Trail or Turbo is enough to get you up speed, especially on inclines. The 130mm front and 120mm rear Rockshox air suspension works well in tandem to soak up bumps and stabilise handling. It’s straight line performance seems so efficient, you’ll find you won’t need to go into Turbo often, and can keep a good steady speed in Trail mode.

Specialized Turbo Tero X load capacity

Of course speed and handling will suffer if the bike is encumbered, but stability is such that we’re sure it won’t spoil the ride. The Specialized Turbo Tero X is designed to take up to 20kg (44lb) of cargo on its rear rack mounts. It can also tow a trailer weighing up to 70kg (154lb) via its thru-axle rear wheel. This gives you plenty of options if taking it out for a wild weekend camping trip. The fenders are particularly sturdy, with no wobble or rattle, and the attached rear 11-lumen light (as well as the front 500-lumen one under the handlebars) come on automatically with the motor.

A close-up view of the Specializes Turbo Tero X drivetrain
Tech spec is impressive, with RockShox air suspension and SRAM drivetrain

The drivetrain is mid-range SRAM SX Eagle, offering smooth and precise shifting. Other small details include a kickstand, frame mounts for a bottle rack and folding bike lock (there are security features in the Mission Control app too). It’s available in silver and gun metal and comes in four frame sizes – small, medium, large and extra large. Specializes says those sizes will suit riders from 155cm to 195cm (5ft 1in to 6ft 5in).

Overall the Specializer Turbo Tero X 4.0 is a comfortable and enjoyable ride that excels on multi-day excursions, but proves its worth as a shopper, communter or kid-carrier too. The key to the Tero X concept is versatility and if you’re looking to stay active, use the car less and keep a little adventure in your life, this could well the only bike you need.

Related content: