Tern Vektron S10 folding bike. Bosch Performance Line & Shimano Deore 10 gears

The Tern Vektron S10 is a compact folding ebike built around the Bosch Performance Line motor and Shimano Deore 10-speed drivetrain, making it a practical choice for riders who need electric assistance combined with portability. This folding bike uses a hydroformed aluminium frame built from 7005-AL, paired with a custom forged crankset and Tern's proprietary engineering across the fold points and steering components. The bike weighs 22.1kg, which is substantial but manageable for storage and transport once folded to 40 × 85.5 × 67.5cm. The fold itself takes around 10 seconds to execute, and the Magnetix 3.0 clip system makes it straightforward to set up and break down.

The drivetrain is straightforward and well-suited to the motor's power delivery. The Shimano Deore shifter works with a Shadow+ rear derailleur to handle the 10-speed cassette (11-36T), giving a gear range from 30 to 97 inches. The chain uses Shimano's DHT design with GST corrosion-resistant coating, which is worthwhile on an ebike that might see regular wet conditions. Shifting is responsive, and the single chainring setup keeps things simple without the complexity or maintenance demands of a traditional front mech. Braking comes from Magura MT4 hydraulic disc brakes front and rear, which offer reliable stopping power even when carrying cargo or a second rider.

The Bosch Performance Line motor delivers 65Nm of torque with a 300% assist level, capped at 25kph in EU markets. The 400Wh PowerPack battery provides a claimed range of 53–106km depending on assist mode and terrain, which translates to roughly 30–65 miles. The Bosch Purion display offers four selectable modes plus walk assist, keeping controls intuitive for daily use. Charging takes place via a standard 220V four-amp charger. The motor integrates into the bottom bracket, keeping the weight low and the bike's proportions relatively balanced compared to hub-motor designs.

The 20-inch wheels run Schwalbe Big Apple tyres (55-406) with puncture protection and reflective sidewalls, which roll comfortably over urban surfaces and rough paths alike. The Kinetix Comp rims with sealed bearings from Novatec hubs keep maintenance minimal. The frame geometry is suited to riders between 147 and 195cm tall, and the adjustable Tern Andros stem allows fine-tuning of the reach. The seatpost is the Tern Telescope model, offering good height adjustment range to accommodate different leg lengths within that rider spectrum.

On the road, the Vektron S10 handles gravel and forest paths competently thanks to the wider tyres and hydraulic disc brakes. The motor makes climbing easier, which opens up terrain that would require more effort on an unpowered folding bike. The compact wheelbase and lightweight construction mean it responds quickly to steering inputs, though the trade-off is less stability at very low speeds compared to larger-wheeled machines. The SKS fenders keep spray off clothing, and the Tern Valo Direct front light (190 lumens) combined with the Herrmans H-Trace rear light provide visibility without relying on separate battery packs.

This bike works well for riders who combine cycling with car hire or ride-share schemes, as you can fold it down and keep it in a vehicle without requiring a roof rack or trailer. The included Rhinowair storage bags protect both the bike and your vehicle interior during transport. The Tern roll-top bags that fit on the Atlas V Rack add practical carrying capacity for work or shopping. The frame is nearly unmarked on this example, having covered just 708 miles since new in September 2023. It was last serviced by Edinburgh Bike Coop in November 2024 and is registered with The Bike Register for security.