Upcoming Triumph Bonneville 400 spied testing again, will rival Royal Enfield Classic 350

Triumph's upcoming Bonneville-inspired motorcycle has been spotted testing once again, and this time the motorcycle appears almost completely undisguised. The latest spy shots reveal several design details and hardware changes, offering the clearest look yet at what is expected to be called the Triumph Bonneville 400.The new motorcycle will expand Triumph's growing 400cc portfolio that currently includes the Speed 400, Scrambler 400 X, Thruxton 400 and the recently introduced Tracker 400. Unlike its siblings, the Bonneville 400 adopts a more traditional neo retro design inspired by Triumph's larger Bonneville range. Triumph Bonneville 400 adopts classic stylingThe spy images show the upcoming motorcycle with a distinctly retro appearance. It gets a sculpted metal fuel tank, a round LED headlamp, a long single-piece seat and wide handlebars that should provide an upright riding position. The overall silhouette closely resembles the larger Bonneville family rather than the sportier Speed 400.Further adding to its classic appeal are wire-spoke wheels, a redesigned radiator grille and an underbelly guard. The motorcycle also appears to feature minimal bodywork, keeping with the timeless retro theme.New suspension setup is the biggest changeOne of the biggest highlights of the upcoming Bonneville 400 is its revised rear suspension. Unlike the Speed 400 and Scrambler 400 X, which use a monoshock setup, this motorcycle features twin rear shock absorbers. The swingarm also appears to have been redesigned to accommodate the dual-shock arrangement.Another noticeable change is at the front wheel, where the disc brake has been repositioned to the right side. Existing Triumph 350cc motorcycles use a left-mounted front brake disc, making this another significant mechanical revision.The test mule also appears to feature a different instrument cluster, although its display functions and connectivity features remain unknown.(Also read: Triumph Tracker 400 Review: Style over substance?)Engine likely to remain unchangedMechanically, the Bonneville 400 is expected to use the same 350 cc, liquid-cooled, single-cylinder engine found in the Speed 400. The motor currently produces 37 bhp and 33 Nm of peak torque and comes paired with a six-speed gearbox featuring a slipper and assist clutch.Triumph could, however, make minor revisions to the engine mapping and gearing to better suit the motorcycle's relaxed and retro-focused riding character.Expected rivals and positioningThe upcoming Bonneville 400 will become the first Bonneville-inspired motorcycle built on the Bajaj-Triumph 400 platform. It is expected to cater to buyers looking for a classic roadster and will likely rival motorcycles such as the Royal Enfield Classic 350, Jawa 350 and Honda CB350.Although Triumph has not confirmed an official launch timeline, the frequency of recent test sightings suggests the motorcycle could make its global debut in the coming months.