Triumph Bonneville T120 Black mileage and running cost

The Bonneville T120 Black is rated at 21 kmpl (claimed mileage). Treat that as a ceiling: real-world figures are usually 15–25% lower.

Among the 40 cruisers we have reviewed it ranks 28th for mileage, 4 kmpl below the group average of 25 kmpl.

At Delhi's petrol price of ₹94.80 a litre and a claimed 21 kmpl, the Bonneville T120 Black costs about ₹4.51 per km in fuel. Ride 30 km a day and that is roughly ₹3,521 a month, or ₹42,254 a year, before servicing.

Spread over five years and 46,800 km, the Bonneville T120 Black works out to about ₹35.8 per km all-in, of which 13% is fuel and 81% is the purchase price itself. Resale value is not counted; expect roughly 50–60% of ex-showroom after five years for a well-kept example.

The quickest wins for the Bonneville T120 Black: keep tyres at the recommended pressure (under-inflation by 5 psi can cost 2–3 kmpl), shift up early, use Eco mode in traffic and avoid idling at long signals.

Short trips hurt most. A cold engine on a 2 km run can return half its normal mileage; if that is your use, expect the low end of the real-world band.

Service on time. A clogged air filter or old spark plug shows up in mileage before it shows up anywhere else.