What’s changed on the new 350cc Triumphs?

Triumph India has updated its 400 lineup with a new 350cc engine. This mill is a result of the GST restructuring that happened in September, 2025, which resulted in the bikes above 350cc being charged with 40 per cent GST and the bikes below 350cc being charged at 18 per cent. To pass this benefit to the customers, Triumph decided to reduce the engine capacity of the 400 lineup in India, from 398cc to 349cc. While on paper it might look like a simple downsizing of the engine, there's a lot more to it. Here's what has changed.

Shorter stroke, similar grunt?

The new Triumph bikes get a new 349cc single cylinder engine with a shorter 56.1mm stroke compared to the 64mm stroke of the 398cc motor that it replaces. While there is a 12.5 per cent reduction in the cubic capacity, Triumph in the press briefing mentioned how they focused heavily on retaining the same character of the bigger 398cc motor. To do so, Triumph has worked on the engine maps to make it more aggressive; the valve timings have also been revised, along with optimisations to the intake system. Triumph has also worked on the balancer shaft for better refinement all across the rev range. Triumph claims the engine has minor fuel efficiency gains, as they have focused more on performance than on efficiency while designing the engine. 

Same same but different

Visually, you won't be able to differentiate the bikes from one another except for one difference. The plaque on the engine now says TR Series instead of TR Series 400cc. The rest of the design, the styling and the colours have been carried over to the 350cc platform, even the naming conventions have been carried over as the bikes would still be named the 400 instead of 350. Triumph has explained that this has been done intentionally to retain the 400cc brand image. Another change is that Triumph has removed the engine immobiliser from all the models in India, while it is available in the international models. 

Price difference Old vs New

The new 350cc bikes will fall under the 18 per cent GST tax bracket and will be significantly less expensive than the current 400cc models they replace. Here's a detailed breakdown of the prices of all the models.