Skip to Main Contents

A&S Clutch

Revs Your Heart – Explore the world of Yamaha motorcycles


What is Yamaha’s Assist & Slipper clutch?

 A clutch connects the engine’s power to the transmission (or “gearbox”); it can transmit or cut the power. It is fitted between the engine and the transmission, and its size and durability for operation differ depending on engine displacement and the characteristics of the specific model.
 The first benefit with Yamaha’s Assist and Slipper (A&S) clutch is that it uses lighter clutch springs so that the clutch lever requires less force to pull in than a conventional clutch for a sport bike. Another benefit is if the gear the rider selects does not match the bike’s speed, the A&S clutch helps keep the bike’s behavior smooth and gentle—two birds with one stone.
 Here’s how it works: Imagine how a wedge functions. Applying the rules of physics, using the sloped face of a wedge allows even a small amount of force to move a heavy object. Put another way, this also means that a large force can be made smaller.
 The “assist” in the name refers to how the clutch makes the clutch lever easier to pull. And to keep the chassis stable when overloaded, the clutch “slips” when engaging, hence it’s called a “slipper clutch.”
 The A&S clutch makes the clutch lever lighter to pull, making the bike more comfortable to ride in the city. And when needed, it can partially disengage from the engine to cancel the force sent to the engine by the rear wheel, making for gentler chassis behavior and a more comfortable and enjoyable ride.


Related Technology

Back to