Triumph Bonneville T40: The Classic Becomes an A2 Single with 400 cc

• 398 cc single-cylinder with 32 hp and 36 Nm, A2-compliant as standard
• Round 4-inch TFT display, map navigation, cruise control and lean-sensitive rider aids
• Prices due in early 2027, deliveries from spring 2027

The Bonneville is one of the most storied names at Triumph. Until now, it has stood in the Modern Classics range for models powered by the Bonneville twin, a two-cylinder engine. The Bonneville T40 and T40 Black change that: both models are based on the 400 cc platform of the TR Series, which Triumph develops together with Bajaj. This means the Bonneville is aimed at riders with an A2 licence for the first time. According to the manufacturer, the T40 is nevertheless not meant to be a stripped-down version, but to carry over the style, finish and riding character of the larger models. For the 2027 new-model season, it is one of the bikes expanding the entry-level segment of classic motorcycles.

What is the Triumph Bonneville T40?

The Bonneville T40 is a classically styled motorcycle with a 400 cc single-cylinder engine that closely resembles the larger Bonneville models. Triumph describes it as the newest member of both the Bonneville family and the 400 range.

Typical features include the sculpted teardrop tank, the round headlight, the longer mudguards and the slim silencer in the so-called peashooter style. The term describes a long, narrow silencer of the kind that was common on British motorcycles in the 1960s. Add to that a classically styled telescopic fork, twin rear shocks and spoked wheels.

The tank features rubber knee pads and the three-bar Triumph badge. According to the manufacturer, the two-tone paint schemes are finished with hand-painted coach lines. Every T40 is to be finished by hand, with a focus on materials, surfaces and small details.

Triumph also opts for a classic look on the engine. The cylinder head has polished cooling fins, and the exhaust header sits in a large, finned clamp. The clutch and alternator covers are made of brushed aluminium. Cables and hoses are routed out of sight so that the engine remains clearly visible in profile. Triumph has embossed the brand name into the handlebar clamp and the front mudguard, and it also appears on the engine covers and in the front and rear lights.

The spoked wheels measure 18 inches at the front and 17 inches at the rear. They combine aluminium rims with steel spokes. This is intended to provide stability while saving weight, which benefits handling.

How do the Bonneville T40 and T40 Black differ?

The two models differ mainly in colours and finishes; the technology is identical. The T40 relies on chrome and brushed metal, the T40 Black on blacked-out parts.

On the T40, the mirrors and grab rail are chrome-plated. The heel guards are made of brushed aluminium and the exhaust system of brushed steel. On the T40 Black, these parts are painted or powder-coated black. It also gets powder-coated engine covers, a blacked-out header and a black peashooter silencer. The rims are gloss black, while the spokes remain silver.

In Europe, the T40 is available in three two-tone combinations:

• Aegean Blue and Fusion White
• Meriden Blue and Tangerine Orange
• New England White and Jet Black

For the North American market, Triumph lists only two of them: Meriden Blue with Tangerine Orange and New England White with Jet Black. The T40 Black is painted in Matt Pewter Grey and Matt Phantom Black.

Which engine powers the Bonneville T40?

The Bonneville T40 is powered by a dedicated version of the liquid-cooled 400 cc single-cylinder engine from the TR Series. According to the manufacturer, it produces 32 hp (23.5 kW) at 7,000 rpm and delivers 36 Nm (26.55 lb-ft) at 5,000 rpm.

The technical data sheet in the German documents lists a different figure of 22.8 kW. What is certain: both models are A2-licence compliant as standard.

Compared with the other 400s, Triumph has revised the cylinder head and developed a dedicated engine calibration for the Bonneville. The aim is more torque in the lower rev range, so the power should be available above all at the engine speeds used in everyday riding. A lower idle speed and an exhaust note tuned for distinct firing pulses are intended to contribute to the relaxed character.

The key technical data at a glance:

• Type: single-cylinder with double overhead camshafts (DOHC) and four valves
• Displacement: 398 cc, bore 89.0 mm, stroke 64.0 mm
• Compression ratio: 12:1
• Fuel system: Bosch sequential multipoint injection with electronic throttle
• Drivetrain: six-speed gearbox, wet multi-plate slip-assist clutch, X-ring chain
• Fuel consumption: 3.45 l/100 km (standard cycle), Euro 5+ emissions standard

The slipper clutch prevents the rear wheel from hopping, i.e. briefly locking and skipping, during hard downshifts. At the same time, the assist function reduces the effort needed at the clutch lever.

What electronics does the Bonneville T40 have?

The T40 has five riding modes, cruise control, as well as lean-sensitive ABS and lean-sensitive traction control. Triumph describes this as equipment that would otherwise be more typical of larger displacement classes.

The three fixed riding modes are called Road, Rain and Eco. In addition, there are two modes that can be configured individually. Each mode adjusts throttle response, traction control and ABS. Preferred modes can be added to a quick-access menu. Lean-sensitive means that the systems take into account how far the motorcycle is currently leaned over. This is meant to provide support even when braking or accelerating in corners.

Round TFT display with Heritage mode

The centrepiece of the controls is a round 4-inch colour display that is fully optically bonded. Riders who like classic round instruments can choose Heritage mode. The display then shows an analogue-style readout designed to recall earlier Bonneville instruments. Gear position, indicators, ambient temperature and fuel level are always visible. Smartphone functions and settings appear in the centre of the screen. Five configurable widgets can be controlled via the backlit switches on the left handlebar.

Navigation and smartphone connectivity

Map navigation is standard and runs via the new Triumph Navigation app. The display shows a full map, speed limits, favourites, points of interest and recent searches. In the app, riders can plan routes in advance, set waypoints, save routes, import them as GPX files and share them with other riders. Calls, contacts and music can also be controlled via the display and handlebar switches without picking up the phone. A USB-C socket in the instrument charges devices on the move.

Lighting and brake warning

The lighting is full LED. According to the international documents, the headlight switches automatically between daytime running light and dipped beam. The indicators are self-cancelling. Under emergency braking, an emergency brake warning makes the tail light flash to alert following traffic.

Chassis, brakes and dimensions of the Bonneville T40

The T40 uses a hybrid spine and perimeter tubular steel frame with a twin-sided steel swingarm. Up front is a 43 mm telescopic fork, at the rear twin shocks with adjustable preload, each with 130 mm of travel.

At the front, a 310 mm disc with an axially mounted two-piston floating caliper does the braking; at the rear, a 255 mm disc with a single-piston floating caliper. Braided steel brake lines are meant to ensure a consistent lever feel. The spoked wheels run tubed tyres in sizes 100/90-18 front and 150/70 R17 rear.

The seat height is 790 mm. With an accessory seat in black or brown, it drops to 770 mm. According to the manufacturer, the T40 weighs 191 kg (421 lbs) ready to ride. The tank holds 14.5 litres. The riding position is upright, with the handlebars and footpegs designed for a natural posture. The ribbed seat is padded for two people. A centre stand is fitted as standard, which should make parking, cleaning and chain maintenance easier.

Further dimensions according to the data sheet: 2,120 mm length, 818 mm width across the handlebars, 1,081 mm height without mirrors, 1,418 mm wheelbase, 25.4 degrees rake and 100.4 mm trail.

How does the Bonneville T40 fit into Triumph’s 400 family?

The T40 is the newest model on the 400 platform, which Triumph launched in 2023 with the Speed 400 and Scrambler 400 X. The Scrambler 400 XC, Tracker 400 and Thruxton 400 have since joined the line-up.

According to Triumph, more than 60,000 motorcycles from the platform have already been sold in over 50 countries. The 400 range is said to have played a key role in attracting new customers to the brand. With the T40, the platform now also gets one of the manufacturer’s oldest model names. The Bonneville name goes back to a speed record that Triumph set on the Bonneville Salt Flats in Utah in 1956.

Steve Sargent, Chief Product Officer at Triumph, describes the ambition as follows: “From the outset, our goal with the T40 and T40 Black was not simply to create a smaller Bonneville, but a motorcycle that delivers the style, character and riding experience that riders expect from a true Bonneville.” He also says that it is strategically important for Triumph to make the Bonneville accessible to more riders, because the smaller-displacement segment is growing worldwide. Working closely with Bajaj, the team tried to retain the proportions, finish and details such as the hand-painted coach lines while bringing more technology into this class.

When will the Bonneville T40 arrive and how much will it cost?

Triumph plans to announce prices for the Bonneville T40 and T40 Black in early 2027. The first motorcycles are expected at European dealers from spring 2027 and in North America from late spring 2027.

An accessory range is to be available at launch, including lower and more comfortable seats as well as classic side panniers. Service intervals are 16,000 km (10,000 miles) or twelve months, whichever comes first. According to the manufacturer, this should lower running costs. In Germany and Austria, Triumph also offers a four-year manufacturer warranty with unlimited mileage at participating dealers.

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