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Tern HSD S9i Gen 3 electric longtail cargo bike in Basalt grey, side profile
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Tern HSD S9i Gen 3

£5,800.00 GBP
ColourBasalt

The Gen 3 Tern HSD S9i — premium HSD with Bosch eShift and PX power

The Gen 3 HSD S9i sits at the top of the HSD range. It runs the Bosch Performance Line PX motor with an upgraded 90 Nm of torque and adds Bosch eShift — wireless electronic shifting that briefly cuts motor power during gear changes and shifts at the ideal point in the pedal stroke, for smooth, effortless gears every time.

It carries the full Gen 3 upgrades: up to 190 kg gross vehicle weight, a longer, more stable wheelbase, a taller Physis handlepost and stronger VLT seatpost for riders up to 205 cm and 130 kg, and Magura cargo brakes — all in a bike that still folds flat for storage and transport.

Made to order — built to your spec. Talk to us about options and lead times.

Book an appointment

Free Click & Collect from our three London shops, or UK-mainland delivery — every bike built & safety-checked. Delivery & collection

Specifications

Tern HSD S9i Gen 3

Best for
Premium one-passenger cargo riding with electronic shifting
Motor
Bosch Performance Line PX
Torque
Up to 90 Nm
Battery
Bosch PowerPack 545Wh
Range
56–103 km (35–64 mi)
Drive
3x3 NINE 9-speed with Bosch eShift and Gates Carbon Drive belt
Display
Bosch Kiox 300 with LED remote
Brakes
Magura hydraulic disc, 180 mm
Wheel size
20-inch
Weight
28.9 kg
Max gross vehicle weight
190 kg
Suggested rider height
153–205 cm (60.2–80.7 in)

Tern HSD S9i Gen 3

Frame and fork
Frame
Tern HSD, 6061-AL, patented design, EN17860 certified: 190 kg
Fork
Suntour custom for Tern, 34 mm stanchions, Thru-axle, EN17860 certified: 190 kg
Cockpit and contact points
Handlepost
Tern Physis 3D, 3D forged, 5 patented technologies, 12°, 320 mm
Stem
Tern Andros, adjustable, forged construction, patented technology
Headset
Tern Flux Pro Taper by FSA, 1.5", angular contact bearings, Physis integrated
Handlebar
Tern Sweep, 6061-AL, Tern Andros adapted
Grips
Ergon
Saddle
Tern by Velo
Seatpost
Tern VLT 40/34.9mm, with Cane Creek suspension and LightAction levers
Seatpost clamp
Tern Collar
Brakes
Front brake
Magura MT4, hydraulic disc, 180 mm rotor
Rear brake
Magura MT4, hydraulic disc, 180 mm rotor
Brake levers
Magura, hydraulic disc
Wheels and tyres
Front wheel
Tern Atlas H, cargo wheel
Rear wheel
Tern Atlas H, cargo wheel
Front hub
Tern Atlas, Boost Thru-Axle, sealed cartridge bearings
Rear hub
3x3 NINE, 9 spd, w/ Bosch eShift
Spokes & nipples
Stainless steel, double-butted
Rims
Tern Atlas H, cargo
Tyres
Schwalbe Big Ben Plus, 55-406, Green Guard puncture protection, Reflex
Drivetrain
Shifter
3x3 CMD, wireless e-shifter, w/ Bosch eShift
Crankset
Tern HSD, Gates CDX CNC machined beltring
Cog
Gates CDX, precision CNC machined cog
Bottom bracket
Motor integrated
Belt
Gates Carbon Drive CDX belt
Pedals
Urban with non-slip surface, sealed bearings
Shifter cable & housing
Wireless
Motor and battery
Motor
Bosch Performance Line PX (BDU34, 600% assist, 90 Nm)
Battery
Bosch PowerPack 545Wh
Display
Bosch Kiox 300 with LED remote, connectivity with Bosch eBike Flow app, electronic bike lock
Range
545 Wh: 56–103 km (35–64 mi)
Charger
Fast Charging, 220V, 4A (EU); 100–240V, 4A (US)
Connect module
Bosch Connect Module with GPS/GSM connectivity & anti-theft alarm when subscribed to Flow+; free 12-month trial upon activation
Equipment
Bell
Pitch Plus, brass
Chainguard
Tern Custom, full chain cover
Kickstand
Ursus, rear mount
Luggage socket
Tern Combo Mount
Front light
Herrmans, 240 lumens
Rear light
Herrmans LED
Fenders
Aluminium, stainless hardware
Rack
Atlas H rack, 6-point mounting, ISO 11243:2023 certified: 80 kg
Frame lock
AXA, keyed-alike with Bosch battery
Fit and capacity
Wheel size
20-inch
Speeds
1 x 9
Gear range
20" - 109" (1.56 - 8.67 m)
Seatpost to handlebar
52–59 cm (20.5–23.2 in)
Saddle to pedal
76–110 cm (29.9–43.3 in)
Suggested rider height
153–205 cm (60.2–80.7 in)
Weight
28.9 kg
Max gross vehicle weight
190 kg

Who the HSD S9i is for

The HSD S9i sits at the top of the Gen 3 range, built for anyone who wants the fullest version of what the HSD can do. Bosch eShift takes care of gear changes on its own — useful on a loaded rear rack through stop-start London traffic — and the 90 Nm Performance Line PX motor gives it the highest torque figure of the three Gen 3 HSD models.

The taller Physis handlepost and longer VLT seatpost widen the fit considerably, up to 205 cm and 130 kg, which matters if the bike is shared between two adults of noticeably different heights, or if you are simply a taller rider who has found cargo bikes cramped before. The Cane Creek suspension seatpost — fitted only on the S9i within the HSD range — adds a further layer of comfort over longer rides or with a passenger on the back.

If wireless shifting and the strongest motor matter less to you than keeping things simple, the P00 and P5i cover the same 190 kg carrying capacity and the same wider rider fit with a more straightforward belt-and-hub drivetrain.

Build & technology

The frame and fork are certified to EN 17860 at the S9i's full 190 kg gross vehicle weight, with a longer wheelbase and lower centre of gravity than the previous HSD generation for steadier handling once loaded. A Suntour suspension fork with 34 mm stanchions takes the edge off London's roads, and Magura MT4 hydraulic disc brakes on 180 mm rotors give dependable stopping power in the wet.

Bosch eShift is the S9i's defining feature — a wireless 3x3 CMD shifter that briefly cuts motor power during a gear change and times the shift to the lowest-torque point in the pedal stroke, so changes happen smoothly rather than under load. It works with the 3x3 NINE hub, a sealed 9-speed system with a 554% gear range, and a Gates Carbon Drive belt that needs no oiling or tensioning.

The Bosch Kiox 300 display and LED remote keep the cockpit uncluttered, and the optional Bosch Connect Module adds GPS tracking and an anti-theft alarm with a Flow+ subscription, with the first 12 months included. The Atlas H rear rack is rated to 80 kg and ISO 11243:2023 certified, and the AXA frame lock is keyed alike with the battery, so one key covers both.

HSD S9i accessories

The HSD accessory system covers passenger seating, weather protection and everyday cargo, and it is built to work across the HSD range. View the full Tern HSD Accessories collection for child seats, rain and sun protection, panniers and racks. Compatibility varies by model and generation, so do check with us, or come in and we will set the bike up around what you actually need to carry.

Not sure the S9i is right for you?

If you are choosing between the three Gen 3 HSD models, the P00 and P5i carry the same 190 kg capacity and the same wider rider fit, in a simpler belt-and-hub drivetrain without electronic shifting. If you are carrying two children rather than one, the Tern GSD is worth a look — or read our HSD hub page for a fuller breakdown of the range.

At Flying Dutchman

We've had the outgoing HSD in the shop for a while now, and eShift is the kind of upgrade that's easier to feel than to describe on a spec sheet. First UK stock is due in September — you can reserve one ahead of arrival, and we'll be in touch as soon as it's ready to ride.

Book a test ride at one of our London shops, or come in and ask us about the Gen 3 range in person.

Tern HSD S9i Gen 3 FAQs

What's the difference between the HSD S9i and the HSD P00 or P5i?

All three share the same frame, the same 190 kg maximum gross vehicle weight, and the same wider rider fit up to 205 cm and 130 kg. The differences are in the drivetrain and motor. The S9i uses the 90 Nm Performance Line PX motor with Bosch eShift and a wireless 3x3 NINE hub — the strongest and most technically involved of the three. The P00 uses a 75 Nm Performance Line motor with a stepless Enviolo hub and Gates belt. The P5i uses the same 75 Nm motor with a Shimano Nexus 5-speed hub and belt. If wireless shifting and the extra torque matter to you, the S9i is the one; if you would rather keep things simpler, the P00 or P5i cover the same capacity and fit.

What is Bosch eShift, and how does it work on the HSD S9i?

Bosch eShift is a wireless electronic shifting system, fitted only to the S9i within the HSD Gen 3 models we stock. Instead of a cable-operated derailleur, a wireless shifter tells the 3x3 NINE hub when to change gear, briefly cutting motor power for around 0.2 seconds during the shift and timing the change to the lowest-torque point in the pedal stroke. In practice, that means gear changes happen more smoothly, with less strain on the drivetrain, even when the bike is loaded and pulling away from a stop.

Can the HSD S9i be shared between different-height riders, or carry an adult passenger?

Yes to both. The taller Physis handlepost and longer VLT seatpost adjust to fit riders from 153 cm up to 205 cm and up to 130 kg, without tools, which makes it a genuinely practical bike to share across a household. The Atlas H rear rack is rated to 80 kg — enough for one child, an adult passenger within that limit, or a substantial amount of cargo. See our HSD hub page for more on passenger and cargo setups across the range.

Can I buy the Tern HSD S9i Gen 3 through Cycle to Work?

Yes, we can usually help with Cycle to Work purchases depending on your employer and scheme provider. Contact us before ordering and we will confirm the best way to arrange it.