How Motorcycle ABS Works

ABS, or the Anti-Lock Braking System, is a word we get to hear on an almost daily basis, but there are rather many fellows out there who don't know exactly what this system does and why they should mind it. The purpose of this short guide is to put some light on how the ABS works in motorcycles.

Apparently, being invented by Gabriel Voisin in the late 20s to solve some braking problems for airplanes, the anti-lock brakes have been used in the automotive industry first. Almost 50 years have passed from the invention of the most primitive designs to the first fully-operational modern-era ABS brakes. 

What does ABS do?

The necessity for a safety system such as the ABS became obvious under hard braking conditions and when having to slow down on slippery surfaces, say wet asphalt. One of the biggest problems of braking hard when riding a motorcycle is the wheel or wheels lock-up.

The role of the ABS is to detect the wheel slip fractions of a second before it would normally occur because of the braking force and adjust or modulate the said force, allowing the wheel to keep turning back within the limits of grip.

ABS pulsar ring in the front wheel helps in detecting wheel speed

So what the ABS does is actually limiting the braking force the rider exerts by either squeezing the lever or pressing the foot pedal and keep the wheel spinning. Once the imminence of the locking (and therefore skidding) is avoided, the system re-applies the maximum braking force until the next skid is anticipated. By limiting the max force of the braking maneuver, the ABS systems practically allow riders to use the greatest stopping force possible without locking the wheels.

How does the ABS know wheels would lock?

While the first ABS brakes relied on purely mechanical components and were terribly imprecise and often showed a very big lag, modern-day electronic technology has made things simpler.

Basically, ABS includes 4 major components: the sensor array, the control unit, the pump and the valves which physically regulate the braking force.

Sensors. While the early ABS technology proved to be unreliable due to a plethora of reading and interpretation errors, the modern systems are equipped with extremely precise sensors, redundant architecture and more safety/ failsafe systems.

ABS Schematics of BMW S1000RR

Here's a video of the working of ABS