The 2027 Triumph Bonneville T40 arrives with a liquid-cooled 398cc single-cylinder engine tuned to make about 30 horsepower, Rider Magazine reports in its first-look coverage of the T40 and T40 Black.
Triumph positions the T40 as a compact Bonneville, carrying classic styling cues such as a teardrop fuel tank, round LED headlight and spoked wheels while using a modern single-cylinder TR-series engine for the 400-class segment, according to Rider Magazine’s first-look piece.
Specifications shown in the coverage list the engine as a 398 cc, liquid-cooled, four-valve single with an 89 mm bore, 64 mm stroke and a 12.0:1 compression ratio; peak output is reported at roughly 30 hp at 7,000 rpm with peak torque in the midrange, reflecting Triumph’s tuning for low-end tractability rather than peak revs.
Triumph Bonneville T40: 398cc single-cylinder powers the 2027 T40
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The T40 Black is described as a darker, more contemporary variant with blacked-out finishes on the engine, exhaust and aluminium elements, while the standard T40 keeps brighter trims. Rider Magazine notes Triumph revealed the T40 as part of a four-model first-look rollout for 2027.
What this means for riders: Triumph’s move puts a modern single-cylinder Bonneville into the under-400cc market, aimed at riders who want classic Bonneville styling with lower capacity, torquier delivery. The first-look coverage says showroom availability and pricing will be confirmed closer to launch in 2027.
Triumph’s announcement of the T40 continues the brand’s strategy of broadening the Bonneville family to reach more riders with a range of displacements and finishes. Rider Magazine’s first-look frames the T40 as the entry point in the 2027 Bonneville range and calls it the first of four new models previewed by the maker.
Sources
- Google News / Rider Magazine (RSS) — first-look coverage of the 2027 Triumph Bonneville T40 and T40 Black, engine and spec details used above
