Bushing reduces the need for maintenance on motorcycle front forks

SKF has developed a composite bushing for motorcycle front suspensions (or forks) that reduces the need for maintenance. A combination of metals, plus a lubricating coating, gives the bushing both mechanical strength and low friction.

“Motorcycle front forks typically require regular maintenance in order to ensure proper functionality,” says Nicolas Berruet, business development manager at SKF. “This bushing helps to overcome that and cuts maintenance to a minimum.”

Beyond reduced maintenance and low frictional properties under side load, the bushing offers a number of other benefits. These include:

• high load-carrying capacity;

• stability across a range of operating temperatures;

• small operating clearance, allowing improved guidance; and,

• dimensions marking for quick product identification.

The steel body of the bushing gives it high mechanical strength, while a PTFE-based self-lubricating sliding layer imparts low friction. To protect the bearings from corrosion, the steel backing is copper-plated. In addition, a thin, intermediate bronze layer creates a strong bond between the backing and sliding surfaces. This helps to dissipate the heat that is generated during operation.

The PTFE-based sliding surface reduces friction, to deliver a smooth riding feeling. During a short run phase, some PTFE material will transfer from the sliding contact surface to the counter face. This material transfer then gives the bushing its characteristic low-friction, low-wear properties.

The fork bushings are supplied as a kit, which allows one fork leg to be serviced completely. The current SKF bushing range is aimed at premium motorcycle applications across the world and is used by OEMs, after-market service centres and end users.