Motorcycle Products:Shock Absorbers (Rear Cushions)

Functions and Roles

Shock absorbers consists of spring which determine posture and cushioning buffer action and a damper which suppresses vibration.
On 2-wheeled vehicles, shock absorbers are separated into the categories of the "front fork" and "rear cushion".
The rear cushion:

  • Maintains posture of the vehicle.
  • It eases the thrust of shocks on rough roads.
  • The rear cushion prevents changes in the contact forces between the rear tires and the road surface, conveys the driving power from the rear tire smoothly to the surface of the road, and creates conditions that conduce excellent traction as it maintains the power of the vehicle and damping capacity.

Types of shock absorbers

Double tube type



Constructed with double tubes, in side is an oil chamber and outside is an air chamber . Have types with low pressurization to obtain further stable damping. Applied from small commuters to large-sized cruisers.

Single tube type

Balance Free Rear Cushion [BFRC]

Balance Free Rear Cushion [BFRC]

Showa's unique "balance-free" structure prevents damping force from being generated across the piston inside the cylinder. With the damping force-generating mechanism placed outside of the cylinder and pressurized, damping force response is improved.

Technological Information [BFF&BFRC-lite]


Pressurized type (single tube type)

Demonstrate high performance due to construction of separate oil and air chambers.
In some smaller vehicles, partitions are not applied ( emulsion type ). Applied to wide range of models.

With pressurizing sub-tank

With pressurizing sub-tank

Basically similar with a singe tube construction, however excellent in heat dissipation.
This type have wide range of settings.

Electronically Equipped Ride Adjustment [EERA]

SHOWA EERA  Balance Free Damping Force

SHOWA EERA Balance Free Damping Force

Showa has independently developed electronically controlled hydraulic valves for motorcycles. In the past, these valves were often converted from automobile use. By adopting characteristics optimized for motorcycles, the product achieves superior operation stability and ride comfort.

Technological Information [EERA]