This research conducted the effect of different ethanol blends in a conventional gasoline engine under various load and speed conditions for its performance and emission characteristics. The experiment was tested on the test motorcycle designed initially to run by gasoline fuel. The experimental procedure was performed in the motorcycle testbed equipped, measuring power, fuel consumption, and exhaust emissions. NOx and HC emissions of the test vehicle using ethanol blends are lower than gasoline. However, NOx emissions have an opposite trend; they increased approximately 7.4% with E5, 12.3% with E10, and 18.51% with E20 due to the temperature increase. Furthermore, the ethanol contents provide the leaning effect to enhance the air-fuel equivalence ratio to a more excellent value and result in the burning closer to stoichiometric. As a result, improved combustion and increased power output are possible.Implications: This paper aims to find out the solution to solve the problem related to the energy crisis and polluted environment from the motorcycles in Vietnam.