It’s pretty tricky to visualise from a text-only description, but the basics go like this:
When you depress your clutch pedal, it pushes the release bearing into the diaphragm spring of the pressure plate.
As the centre of the spring moves towards the clutch plate and flywheel, the outer edge moves further away, releasing the contact of the pressure plate and clutch plate.
Without the necessary force sandwiching the clutch disc between the pressure plate and flywheel, the clutch plate is free to slow down and stop spinning. The driver can now safely change gears by releasing the engine power from the clutch plate and transmission shaft.
As we said, it’s not easy to visualise the exact mechanics if you’re not an engineer or a mechanic. So, to make life easier for you—and clutches simpler to understand—why not watch this great cutaway video showing exactly how a clutch kit works.
Why can changing a clutch kit be so costly?
Given clutch kits aren’t horrifically expensive to buy (check out some manufacturer’s clutch kit prices and how we determined our average price of £235), it’s often the time-consuming process to change your clutch that adds cost to the job.
Replacing a clutch kit costs between £300 and £700, with the average coming in at £475. You might need to add the price of a flywheel in there too, and a gearbox oil flush to keep everything silky-smooth. However, it’s down to it being at least half a day’s work to access a clutch for removal that explains away those often-high costs.
Many vehicles will need the engine lifted or dropped to crack the engine and gearbox apart, as that’s where the clutch sits. Separating those major components is a pretty meaty job and why replacing your clutch kit is such a labour-intensive operation.
Performance clutch kits
If your vehicle operates under less than typical conditions—for example, if it tows heavy loads, trailers, is a sports model or an off-road vehicle—then there’s a chance it could need a little extra help. Performance kits come under many guises, so selecting the correct option for your make and model and the job it undertakes is essential.
In such performance clutch kits, you’ll often find that the clutch plate is made of carbon or ceramic material, delivering the level of friction required of high-performance engines.
Of course, high-performance vehicles don’t just operate on bigger engines but their weight to power ratios. With that in mind, some performance clutch kits will include the addition of lightweight aluminium flywheels instead of the traditional heavy-duty steel part.