Drivetrain Systems

Drivetrain Systems

The side gear assembly and final gear assembly are a part of the power transmission device in a shaft drive motorcycle system. The driving force generated by an engine is transmitted to the tires through the side gear (bevel gear), the drive shaft, and the final gear (bevel gear). These gears play an important role with regard to the changes in the rotational direction generated by the engine and the acceleration and deceleration adjustments in the RPMs. When compared with chain-drive motorcycle systems a larger amount of power can be conveyed along with the effectively silencing, and reducing frequency of maintenance.

Technical illustration of motorcycle drivetrain systems

SHOWA's Approach

Durability, quiet operations and minimization and reduction a weight are all demanded of drivetrain parts for motorcycles. In order to satisfy these demands, Showa provides support to optimize gears specifications, strength, and improve durability.

Side gear assembly


Product picture of a side gear assembly drivetrain system

This component changes the direction of the output revolution of motorcycles by 90 °, and transmits the power to the final gear assembly through a drive shaft. Adoption of aluminum as the material for the case has led to a reduction in weight.

Final gear assembly


Product picture of a final gear assembly drivetrain system

Changes the direction of the power transmitted from a drive shaft, decelerate, and conveys it to the rear wheels. Changes in the power transmission device from a chain to a final gear assembly to make it maintenance-free.