3. CLUTCH PLATE
The clutch plate is a disc that slides over the gearbox input shaft. The spline or teeth at the centre of the clutch plate match the teeth of the gearbox input shaft. When the clutch plate slides over the shaft, the matching spline teeth mean the clutch plate is keyed or locked into the gearbox input shaft, and is positioned flat to the flywheel.
Around the outside of the clutch plate, on both sides, there is a hoop of friction material. The friction material riveted to the disc is designed to grip the flywheel. Because of the interlocking spline, the clutch plate and gearbox input shaft will then turn together
‘When things rub together friction comes into play. In some cases you don’t want friction, so a lubricant is used. In other cases you want the friction and use materials to maximize it to achieve grip. Examples of friction material include brake pads, tyres and the material on clutch plates.’
4. COVER ASSEMBLY
The cover assembly bolts to the flywheel and over the clutch plate. The purpose of the cover assembly is to carry the matching surface (a heavy metal casting) for the flywheel, and a spring loaded system that pushes the casting towards the flywheel. Together the cover assembly and flywheel work just like a vice and work together to clamp down onto the friction material of the clutch plate. When the cover is bolted to the flywheel, its default position is clamped. The vice is tightly clamped onto the clutch plate.