FZ-S Fi

2021 Yamaha FZ-S Fi Technical Analysis & Specification Breakdown

Engineered by Yamaha for the naked motorcycle segment, the 2021 Yamaha FZ-S Fi utilizes a 149 cc (9.1 cu in) air-cooled single cylinder, four-stroke layout. In factory specification, peak output is rated at 12 HP (8.8 kW) at 7,250 rpm while maximum torque reaches 13.3 Nm (9.8 lb-ft) at 5,500 rpm, transferring power to the rear wheel through a 5-speed gearbox and chain final drive. With a specific output of 80.5 HP per liter and a 1,750 rpm working window between peak torque (5,500 rpm) and peak power (7,250 rpm), the engine character is indicating a tractable, stress-free state of tune focused on everyday usability and broad torque delivery.

On the scales, the FZ-S Fi measures 135 kg (298 lbs) wet (curb), translating to a power-to-weight ratio of 0.09 HP/kg (11.25 kg per horsepower). Rider ergonomics and chassis geometry center around a 790 mm (31.1 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance, combined with a 1,330 mm (52.4 in) wheelbase engineered for quick, flickable steering geometry. The 13-liter (3.4 US gal) fuel tank supports practical everyday commuting and weekend road stints.

Within MotoLibrary's Yamaha archive, this model family spans 4 indexed model years from 2020 to 2023, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.