Slipper clutch
Encyclopedia
A slipper clutch is a specialized clutch
developed for performance oriented motorcycle
s to mitigate the effects of engine braking
when riders decelerate as they enter corners.
They are designed to partially disengage or "slip" when the rear wheel tries to drive the engine faster than it would run under its own power. The engine braking forces in conventional clutches will normally be transmitted back along the drive chain causing the rear wheel to hop, chatter or lose traction. This is especially noted on larger displacement four-stroke engines, which have greater engine braking than their two-stroke or smaller displacement counterparts. Slipper clutches eliminate this extra loading on the rear suspension giving riders a more predictable ride and minimize the risk of over-reving the engine during downshifts. Slipper clutches can also prevent a catastrophic rear wheel lockup in case of engine seizure or transmission failure. Generally, the amount of force needed to disengage the clutch is adjustable to suit the application.
Slipper clutches have been used in most high displacement four stroke racing motorcycles since the early 1980s. Slipper clutches were introduced in the 1970s by John Gregory and TC Christenson on "Hogslayer" the most successful drag racing motorcycle of the 1970s. Made of bronze sintered plates from an earthmover and a Rambler 2 speed transmission, the drivetrain let TC reach 180 mph in the quarter mile. Slipper clutches are used on many current sport bike
s.
Slipper clutches have also been used to a lesser extent on automobiles, primarily those powered by motorcycle engines. They can also be found on racing remote control cars. Some experimental aircraft
use a slipper clutch to protect the engine from shock in the event of a propeller strike. A slipper clutch for an automobile was patented with a French priority date of 1953 to J.Maurice ETAL [US patent 3072234.] The principle of this slipper clutch was exactly the same as found in modern motorcycles
One-way sprag clutches have also been used for the same purpose, but are generally not adjustable for disengagement force. Early Honda Shadow models used a design wherein a sprag clutch is connected to just half of the clutch friction plates, allowing the clutch to slip during heavy backloading sufficiently to prevent rear-wheel lockup, while still allowing moderate engine compression braking with the remaining friction plates.
Clutch
A clutch is a mechanical device which provides for the transmission of power from one component to another...
developed for performance oriented motorcycle
Motorcycle
A motorcycle is a single-track, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.Motorcycles are one of the most...
s to mitigate the effects of engine braking
Engine braking
Engine braking is where the retarding forces within an engine are used to slow a vehicle down, as opposed to using an external braking mechanism, for example friction brakes or magnetic brakes....
when riders decelerate as they enter corners.
They are designed to partially disengage or "slip" when the rear wheel tries to drive the engine faster than it would run under its own power. The engine braking forces in conventional clutches will normally be transmitted back along the drive chain causing the rear wheel to hop, chatter or lose traction. This is especially noted on larger displacement four-stroke engines, which have greater engine braking than their two-stroke or smaller displacement counterparts. Slipper clutches eliminate this extra loading on the rear suspension giving riders a more predictable ride and minimize the risk of over-reving the engine during downshifts. Slipper clutches can also prevent a catastrophic rear wheel lockup in case of engine seizure or transmission failure. Generally, the amount of force needed to disengage the clutch is adjustable to suit the application.
Slipper clutches have been used in most high displacement four stroke racing motorcycles since the early 1980s. Slipper clutches were introduced in the 1970s by John Gregory and TC Christenson on "Hogslayer" the most successful drag racing motorcycle of the 1970s. Made of bronze sintered plates from an earthmover and a Rambler 2 speed transmission, the drivetrain let TC reach 180 mph in the quarter mile. Slipper clutches are used on many current sport bike
Sport bike
A sport bike, also written as sportbike, is a motorcycle optimized for speed, acceleration, braking, and cornering on paved roads, typically at the expense of comfort and fuel economy in comparison to less specialized motorcycles...
s.
Slipper clutches have also been used to a lesser extent on automobiles, primarily those powered by motorcycle engines. They can also be found on racing remote control cars. Some experimental aircraft
Experimental aircraft
An experimental aircraft is an aircraft that has not yet been fully proven in flight. Often, this implies that new aerospace technologies are being tested on the aircraft, though the label is more broad....
use a slipper clutch to protect the engine from shock in the event of a propeller strike. A slipper clutch for an automobile was patented with a French priority date of 1953 to J.Maurice ETAL [US patent 3072234.] The principle of this slipper clutch was exactly the same as found in modern motorcycles
One-way sprag clutches have also been used for the same purpose, but are generally not adjustable for disengagement force. Early Honda Shadow models used a design wherein a sprag clutch is connected to just half of the clutch friction plates, allowing the clutch to slip during heavy backloading sufficiently to prevent rear-wheel lockup, while still allowing moderate engine compression braking with the remaining friction plates.