WAD SUSPENSION ELEMENT.
WAD refers to “travel related damping” – a principle that has its origins in offroad sport. BMW Motorrad has adopted this principle and developed it further. This innovative damping system on the rear strut enhances considerably the suspension comfort and safety, specifically in extreme situations.
Wheel suspension systems in motorcycles essentially perform two tasks: they must react to the slightest unevenness in road surfaces and bumps, keeping any risk of impact as far away as possible from the suspension. This applies specifically when the motorcycle is fully upright under the weight of the rider and equipment. Here, about a third of the total spring travel is used. The suspension and damping system must react harder when the rider is accelerating powerfully – as it must for bumps and uneven surfaces.
Even if the spring travel is almost completely used up, the suspension element should not bottom out. This is described as a progressive suspension and damping curve. BMW motorcycles with the WAD suspension element integrate this in the form of progressively wound springs and a strut connected obliquely to the paralever. The spring tension is adjusted conveniently at a dial for various rider, pillion, and luggage weights. The adjustment is continuously variable and effected hydraulically.
The WAD suspension strut also has a damping system whose power increases in the compression stage, i.e. with increasing deflection. It also allows the damping curve at both the rebound and the compression stages to be adapted precisely to the vehicle type and use. The design potentially allows an increase to compression by more than 100%, and the rebound can be increased by 50%. This patented BMW Motorrad damper system embodies a function that stands out clearly from conventional systems.
Parallel to the main piston of the damper system, an auxiliary piston inside the hollow piston bore provides additional damping. Both the WAD suspension strut and the struts without travel related damping allow the rider to adjust the rebound characteristics to his riding style on or off the road.