If power steering is now a normal driving aid for cars, this is not the case when you think of motorcycles. However, Yamaha wants to overturn “dogma”, and in fact has announced which is developing an electric steering assistance system for motorcycle applications which he will test on his models participating in the Japanese motocross championship.
What Yamaha has announced is a first concrete step in the development of this technology: steering assistance via an EPS device (Electric Power Steering), that is an electric power steering for motorcycles, which performs more than one function. The EPS system is a relatively compact unit that it is mounted on the triple upper shaft. It uses a magnetostrictive torque sensor, similar to those that manage traction on pedal-assisted bicycles, says Yamaha, and which are also used in the automotive field to detect steering column rotation when the steering wheel turns. This system then uses its own ECU to decide how much torque to add to aid in handlebar movement.
Yamaha EPS
Yamaha power steering will become essential for moving the bike at low speed
At low speeds, it will act like a car’s power steering and assist the driver’s steering commands. At high speeds it transforms into an electronically adjustable steering damper that prevents the handlebars from turning too fast, eliminating clicks in the name of safety and stability.
Of course, magnetorheological adjustable and even electronically controlled steering dampers have been around in the motorcycle world for decades. But the key difference with the EPS system is its ability to actively assist steering at low speeds. Yamaha says it “will improve agility, reduce rider fatigue and more”.
The control device, the electric motor and its transmission, they have a small footprint and can find space on existing frames, while the small control unit is also easily positioned on the bike.
A simple system like this could end up replacing traditional fluid-based steering dampers without adding a lot of cost, while giving Yamaha the ability to use the handlebar width without sacrificing any handling when cornering. Yamaha has therefore declared that it wants to equip a wide range of models with its EPS system. When this will happen it is not clear and we will certainly have to wait for further tests on “road” bikes to understand the goodness of the system.