RS-1 Evolution Racing

2003 Rieju RS-1 Evolution Racing Technical Analysis & Specification Breakdown

Engineered by Rieju for the sport motorcycle segment, the 2003 Rieju RS-1 Evolution Racing pairs a 50 cc (3.1 cu in) single cylinder, two-stroke architecture with road-focused gearing. In factory specification, peak output is rated at 8 HP (5.8 kW). With a specific output of 160 HP per liter, the engine character is placing it firmly in high-revving supersport territory where top-end breathing dominates.

On the scales, the RS-1 Evolution Racing measures 87 kg (192 lbs) dry, translating to a power-to-weight ratio of 0.09 HP/kg (10.88 kg per horsepower). Rider ergonomics and chassis geometry center around a 800 mm (31.5 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance. The 8-liter (2.1 US gal) fuel tank supports practical everyday commuting and weekend road stints.