2027 Triumph Bonneville T40 First Look: 14 Fast Facts; 24 Photos

Don Williams

October 22, 2026

2027 Triumph Bonneville T40 First Look: 14 Fast Facts; 24 Photos

Triumph has added a single-cylinder Bonneville to its lineup. The 2027 Triumph Bonneville T40 and the darker T40 Black join the company’s 400 line, powered by a retuned version of the 398cc TR Series engine from the Speed 400. The T40 has a 31.1-inch seat height and weighs 421 pounds ready to ride, and it comes with an array of electronic rider aids. Triumph will reveal pricing early in 2027, and the first bikes reach US dealers in late spring 2027. Here is what Triumph is bringing to the marketplace:

The styling follows the bigger Bonnevilles. The teardrop fuel tank has rubber knee pads, the three-bar Triumph badge, and coach lining, a thin contrasting stripe painted on by hand. The headlight is round and LED, the fenders are long, and the exhaust ends in a peashooter silencer. The engine’s cylinder head has machined fins, and the clutch and alternator covers are brushed aluminum. Cables and hoses are routed out of sight, and Triumph branding is embossed into the handlebar clamp and front fender. Each bike is finished by hand.

Every Bonneville before the T40 has used a parallel-twin engine. Today’s Bonnevilles use 900 and 1200 twins, and the T40 brings the name to Triumph’s 400 range. “The Bonneville is one of the most significant motorcycles in Triumph’s history, so introducing a new model carrying that name comes with a responsibility to get it right,” says Triumph Chief Product Officer Steve Sargent. “From the outset, our ambition for the T40 and T40 Black was not simply to create a smaller Bonneville, but to create a motorcycle that delivers the style, character, and ownership experience riders expect from a genuine Bonneville. Bringing that experience to more riders is strategically important for Triumph, particularly as lower-capacity motorcycle categories continue to grow around the world.”

Triumph retuned the 398cc single for pulling power at lower rpm. A revised cylinder head and a Bonneville-specific tune put the T40’s peak torque of 27 lb-ft at 5000 rpm. The Speed 400 makes 28 lb-ft at 6500 rpm, so the T40 reaches nearly the same pulling force 1500 rpm sooner. Peak output is 30 horsepower at 7000 rpm, about 10 horsepower less than the Speed 400’s 39.5 horsepower at 8000 rpm. Triumph says the tune puts the emphasis on everyday engine speeds. The liquid-cooled engine has double overhead cams, four valves, and Bosch fuel injection. Triumph also lowered the idle speed and tuned the exhaust for a distinct sound.

Five riding modes change how the bike responds. Road, Rain, and Eco are preset, and two more modes can be set up by the rider. Each mode adjusts throttle response, traction control, and ABS. Riders can choose which modes appear in a quick-access menu on the display. Cornering ABS, cornering traction control, and cruise control are standard on both the T40 and T40 Black. Triumph’s Optimized Cornering ABS and Optimized Cornering Traction Control take lean angle into account, which increases safety in corners.

A 6-speed transmission works with an assist-and-slipper clutch. The assist function uses ramps to draw the clutch plates together under power, which allows softer springs and a lighter pull at the lever. On an aggressive downshift, the slipper function lets the plates slip to limit rear-wheel hop. Final drive is by X-ring chain. A center stand is standard, which makes it easier to store the bike upright, clean it, and lubricate and adjust the chain.

The chassis is built around a tubular steel frame. It combines spine and perimeter designs, and a steel swingarm guides the rear wheel. The suspension has no damping adjustment and allows 5.1 inches of travel at each end. The shocks are adjustable for spring preload to account for a passenger or cargo. The wheelbase is 55.8 inches, with 25.4 degrees of rake and 4.0 inches of trail.

The aluminum-rimmed wire-spoke wheels wear MRF tires, and Brembo’s Bybre brand brings the calipers. The tires are a 100/90-18 Zapper FH in the front and a 150/70-17 Steel Brace SC-01 rear. Although they are tubeless, old-school tubes are required due to the rim design. The retro-style 18-inch front rim limits the choice of replacement tires, and the sizes match the Bonneville T100’s, so there is still a decent selection. A 310mm disc and 2-piston caliper handle front braking. Steel-braided brake lines carry the hydraulic fluid for a consistent and precise feel at the lever. The rear brake pairs a 255mm disc with a single-piston caliper. The taillight flashes during heavy braking to alert drivers that the bike is slowing quickly.

Ready to ride, the T40 weighs 421 pounds, and the seat sits 31.1 inches from the ground. The traditional padded bench seat is ribbed and accommodates a passenger. The riding triangle is upright and neutral thanks to the positioning of the grips and footpegs relative to the seat. An accessory seat in black or brown lowers the seat height to 30.3 inches, and a comfort seat is also offered.

The fuel tank holds 3.8 gallons. Triumph’s EU-test figure of 68 mpg works out to about 260 miles per tank. If you’re looking to turn the T40 into a weekend tourer, classic panniers are among the Genuine Triumph Accessories available.

A configurable 4-inch color TFT display sits inside a round instrument housing. The standard screen shows gear position, turn signals, ambient temperature, and fuel level, and the center of the screen handles phone functions and bike settings. Heritage Mode swaps that layout for an analog-style display modeled on traditional Bonneville gauges. Five customizable widgets give quick access to the functions a rider uses most, and they are run from the backlit switch housing on the left side of the handlebar. Wireless smartphone connectivity is standard. Riders can answer calls, open contacts, and control music from the switches without handling the phone. A USB-C socket charges a phone or other device while riding. Lighting is all LED, and the turn signals are self-cancelling.

Full map navigation is standard through the new Triumph Navigation App. The TFT shows a full map view and speed limit information, and favorite destinations, points of interest, and recent searches can be pulled up on the display. In the app, riders can plan routes before leaving, discover new routes, add waypoints, and manage trip details. Routes can be saved, imported as GPX files, and shared with other riders, with the directions then displayed on the bike’s screen.

The T40 and T40 Black differ only in finish. The T40 comes in two-tone Meriden Blue and Tangerine Orange or New England White and Jet Black. The mirrors and grab rail are chrome, the heel guards are brushed aluminum, and the steel exhaust is brushed. The T40 Black is painted Matt Pewter Grey and Matt Phantom Black, and it has gloss-black rims with bright steel spokes. Its engine cases are powdercoated, the header and silencer are blacked out, and other components are painted or powdercoated black.

The T40 joins a platform that has sold more than 60,000 motorcycles in more than 50 countries. Triumph partner Bajaj Auto builds the 400 range in India. The T40 is the sixth model in the line, alongside the Speed 400, Scrambler 400 X, Scrambler 400 XC, Thruxton 400, and the new Tracker 400. Triumph says the 400s have brought new riders to the brand and contributed to its record global sales. “Working closely with Bajaj,” Sargent explains, “we challenged ourselves to retain the details and qualities that make a Bonneville special, from the proportions and finish to traditional touches such as hand-painted coach lining, while also introducing a level of technology and rider-focused innovation not previously seen in this category.”

The 2027 Triumph Bonneville T40 is not meant to compete with the Speed 400. About 10 horsepower was surrendered by the T40 to move the engine’s pull lower in the rev range. Then, the T40 was loaded with electronics: cruise control, cornering ABS and traction control, adjustable riding modes, and full map navigation. The rest went into paint, polish, and styling riders already know. The open question is price, which Triumph will announce early in 2027. Current 400s range in price from $5495 for the Speed 400 to $6895 for the Scrambler 400 XC.