Posted: March 29, 2017
Outside of “Mr Clutch” you’ll be hard pressed to find a person, or group of people that spend a great deal of time thinking about that ‘thing’ typically operated by the pedal underneath your left foot that makes gear change possible. But clutches are an integral part of most vehicles (even those with an automatic transmission) and so it pays to know a bit about how they work so you can preserve the life of yours and save yourself a costly trip to the garage.
Simplified massively, a clutch has two discs. The first is a steel flywheel which you’ll see on the left of this image. This is attached to the crankshaft (the crankshaft converts the linear motion of the pistons into rotational energy).
The second is the clutch disc, also known as a splined friction disc or centre plate. This transmits drive from the engine to the gearbox input shaft. There’s also a pressure plate containing a sprung mechanism which is bolted to the flywheel to clamp the friction disc to the flywheel and onwards to an actuating mechanism.
In its resting position (i.e. before you put your foot on the clutch), the two discs are tightly clamped together. The action of putting your foot on the clutch releases the force generated by the pressure plate, enabling them to move apart. In doing so, you momentarily disengage the drive from the engine to the gearbox which allows you to change gear. Once you take your foot off the clutch pedal, the clamping force is reapplied and drive is resumed.
In modern racing cars and high performance road cars, it’s common to see a twin disc clutch. This includes two friction plates and gives double the clamping power when re-engaging with the flywheel. If you’re dealing with a car with over 500 horse power this is extremely beneficial, though it’s likely you’ll need to push down twice as hard on the clutch pedal to change gear.
Shortening the life of your clutch
If you’re someone who finds hill starts or parking in tight spaces a challenge, you may have been in situations when your engine is delivering sky-high revs but the car is only moving forward or backwards at one or two miles per hour. Typically in this situation, the driver has the clutch semi-depressed and that means that although the friction disc and the flywheel have come together, the lack of pressure between them is causing the discs to slip. If you’re finding the situation particularly challenging and it’s taking you quite a bit of time to get the manoeuvre done, you’ll probably start to smell the clutch burning as the friction between the slipping discs heats up the components. The unwanted heat soaks through the hydraulic actuating cylinder and could cause the hydraulic seals to give out. Even if this doesn’t happen, slipping the clutch in this manner can be compared to sanding down a piece of wood with a piece of glass /sand paper. Initially the paper is rough and full of grip, but as time goes on, the grip is worn away and you’re left with a smooth friction disc which is unable to grip the flywheel to create drive.
And that’s not the only situation where as a driver, you could be at risk of wearing your clutch. It’s important to pay particular attention to how early you press the gas down at the end of each gear change. Get on the gas too early before the friction disc is fully clamped to the flywheel and you will have a similar problem with clutch slip, friction, heat and a shortened clutch life.
Should I religiously push the clutch pedal all the way to the floor every time I change gears?
Every clutch will have a different bite point, some a lot lower than others. When driving on the road or on circuit you need to apply enough pressure and subsequently allow the pedal to travel far enough, to allow the friction disc to “free wheel” independently of the flywheel. If this is not achieved the clutch will “drag”. You’ll know if your clutch is dragging because you will find it difficult to engage gears because the gearbox is still rotating - albeit slowly. This typically results in the driver forcing the car into gear, potentially wearing out gearbox internals as well as shortening the life of the clutch.
I’ve heard you can perform a “clutchless gearshift” – how is that possible?
Yes, a clutchless gearshift is possible but definitely not recommended. Clutchless shifts require that the gear you are currently in and the gear you’re changing into are at a matched speed. This can only really be done at a low to moderate engine speed. The faster you go, the more difficult it becomes and of course, the amount of trial and error required to accomplish the task risks causing damage to your gearbox and drive train. There’s the safety aspect too. Your decision to change gear should be based on road conditions. If you’re having to focus your brain on matching gear speeds to accomplish a clutchless shift, you definitely won’t be thinking about planning for the hazards on the road ahead. Performing a clutchless gear change takes more time than an ordinary shift too, so that means more time with your hands off the steering wheel and a greater likelihood that you’ll end up coasting as the gear fails to engage, adding further to the demands on your concentration and cognitive skills.
If your driving promotes smooth precise gear changes and a considered application of the accelerator pedal, worry not. However if you’re missing the odd gear, feeling the revs rise but not getting an appreciable feeling of forward momentum, or visiting the garage too often for clutch changes, it may be time to take a look at your driving technique. Our core skills driving course could be just what you need.
These courses are designed to make the most of the driving skills that all of us aspiring (performance) drivers hope we have lurking within us. Colin (and his team) seem to have acquired a vast range of skills and experience to tease this out of even the tardiest of learners. He is keen to see potential problems from the individual’s perspective rather than his own. The courses involve discussion of the forces, vectors, and accelerations involved and their effects on the tyres, suspension and car both in theory and on the track. These aren’t always as obvious as I had previously thought. Colin also seems to be well aware that the learning of ‘new’ motor skills requires repetition, repetition and more repetition till it becomes innate. This differs from other courses where you are shown once or twice and then expected to be able to reproduce it for evermore, both an unrealistic and naïve expectation. The repetition was far from boring, quite the opposite because when I finally was able to reproduce what was required without much effort again and again it was a Hallelujah moment. Progress. Colin is an uncommonly modest bloke whom you have to press to share his credentials for the job which turn out to be impressive and include engineering, test driving, racing as well as teaching for luminary individuals and multinational motor companies. The delivery of his instruction was neutral even though he might have been telling you the -----ing obvious for the nth time which I know I certainly would not be able to do. What I failed to understand at the end of the courses was why this was so little known about. It should be mandatory for all drivers irrespective of their apparent knowledge base or experience. For those who have invested heavily in their offspring who have recently passed their driving test it would seem short sighted not to see this through by enrolling them on the TL1. It could save their lives and seems a small price to pay for the absence of much potential heartache. Highly recommended.
"Cat Driver Training - September 2021 If you want to understand and explore the dynamics of your car then this is the team to help you whatever your level of knowledge. Personally I learnt many things about the dynamics and capabilities of the Porsche 911. Things that had not been explained to me in such detail even on Porsche factory tours and track events. The level of instruction out on the handing circuits and tracks is of the highest standard and brings to life the theory discussed in the classroom. My driving skills were taken to the next level and I will continue to work with CAT to further develop them. The facilities available at Millbrook are outstanding and it is a privilege to be able to access them via CAT Driver Training."
"Do you think you know it all? Well set up, well briefed and spendidly delivered. This training covered technical aspects of driving skills and then followed (and backed) those up with practical exercises. The learning was continuous and developmental. Whether it was simply understanding what your car could do (or what you might be able to make it do) or what you could do, there was a whole range of skills, techniques and aids that would enhance anyone's understanding of motoring. Whether it was how ABS could be triggered (or not), understeer/oversteer, trial braking, dynamic forces, on-limit driving; you name it, this course covered it. Delivered by people who clearly knew what they were talking about, but in a friendly, clear and accommodating style. I learned something from every session."
"The best decision I ever made! I have trained with CAT Driver Training twice now & looking forward to coming back in the future. I trust in their expertise & there is always something new to learn, a habit to be explored & an exhilarating experience that pushes me to my limit & builds confidence in myself & the car. The knowledge, experience, understanding, patience, compassion & professionalism of the team are just some of the qualities that make them unique & I highly recommend them."
"Performance Driver Track Day Course I participated in the course arranged by Porsche Club GB and very happy to give 5 stars all round. The team has put a huge amount of thought and effort into making the facilities and training Covid-secure, which is indicative of their professionalism. I found the whole day both fascinating and a lot of fun, in briefings, on the various driving segments, and chatting with the team and other participants. I was genuinely in awe of how much Colin moved my theoretical and practical driving on, and what he got me to get the car to do in the space of one day - always building confidence, encouraging me to explore my limits, while not pushing me beyond them. Can't wait to return!"
"I have had a reasonable degree of driving training over the years as am ex police officer and advanced police driver. I took the performance driver driver training to learn about track driving, and found it excellent. My instructor was Paul who was fantastic. The training built up during the day and I learnt so much about the capabilities of my own car and although I was nervous about using my own car realised afterwards it was the best thing for me to do. The instruction was extremely informative from an engineering perspective coupled with driving, friendly and tailored to your individual needs and abilities. At no time was I encouraged or pushed to do anything I wasn’t comfortable with. It was extremely professional throughout. I would thoroughly recommend this to anyone whatever your standard of driving."
"Truly exceptional In my experience, driving instruction has generally consisted of being repeatedly told that you are 'doing it wrong' accordingly to some unknown standard or principle that you had hoped to learn about by taking said instruction. Then there is Colin. It is not that common to find an individual who genuinely understands both people and engineering. It is incredibly rare to find one who can actively apply both to deliver a sustained behavioural change. Colin adapts his teaching style to the way you learn. For me, he lead with the WHY of the learning point, grounded in physics and engineering. We'd then put it in to practice, often doing several variants of an excercise to explore how the car reacts to differing inputs, providing valuable context for what good feels like and reinforcing the learning point. Each point built on the previous ones, layering up and coming together in to a whole, one far greater than the sum of it's parts. Subtle changes to huge effect. I was concerned on the day that the learnings would rapidly fade, but I have found that because Colin has taught me an understanding the lessons have persisted, even if I do still need some more practice (48 laps of the Silverstone GP circuit last Thursday definitely helped!). Add to this the fact that Colin is great company and an absolute pleasure to spend time with, and you have one of the most positive learning experiences I've ever known. Truly exceptional. I could not recommend more highly. Thank you!"
"Superb day with calm knowledgable and professional guidance from Paul. Thank you Paul. The course is so well structured consistently building ability and knowledge in complete safety. I fully recommend anyone wishing to increase their knowledge, confidence and experience to attend."
"Far better than any track day you can imagine! There is a massive difference between a typical driver experience or track day events and CAT driver training. The main difference is that you drive your own car to the full extent of it's capabilities, and your own, while being given expert one to one tuition by brilliant trainers Colin and Paul, who come from a Motorsport and auto engineering background. Their combined domain knowledge of engineering and competitive Motorsport allows them to explain the physics of why the car behaves as it does and how you can exploit the cars characteristics for maximum performance., in a safe fun environment. The frankly brilliant experience on the track is matched by the quality hospitality hosted by Jo, and classroom training, which prepares you for what you will experience on the next stage. These stages include such delights as the ring, where you will drive with no hands on the wheel at 100MPH, providing you with a clear understanding of the fact the car finds its own balance , and my personal favourite the alpine stage, with hairpins a plenty and 'character building' drops and rock faces. I have to admit to being slightly 'corner shy' before the training, however after some brilliant coaching from Collin urging me to 'stay on the gas, stay on the gas!' I am now far more confident and safe in the twisty stuff!"
"I don’t want to make this review too long and detailed, so I think the best way to summarise it is this: I think I possibly learnt more in one day that I’ve ever learnt before and the skills are relevant to all driving and can be practised daily. On the way home, I drove the ‘long way’ just to practise and feel the difference in the attitude of the car. I used to do this now and again because there are a few good straights and it’s nice to give the car a ‘blast’. This time, I drove that way home because I wanted to drive round the corners properly."
"Extremely professional driver training. Period. I wanted a course that would deliver a very high level of training, in an organised and professional manner. The course exceeded my expectations in every way, I wish I had started working with CAT Driver training years ago. There is no doubt that if you are looking for absolute top level training, there isn't anywhere else to look. Somehow they manage to follow a very tried and tested course structure, yet it is tailored all the way along to meet your requirements and current skill set. very impressive. I cannot rate this company highly enough. I have more dates booked already."
"Very structured training Paul was very clear and methodical in his coaching. The training technique was built up in various sections during the day and all came together like a jigsaw puzzle in the end for a great result."
"It's hard not to be enthusiastic about the lasting impact CAT Driver Training will have on your approach to driving. I spent a day with Paul exploring the potential of my new vehicle. The coaching is clear, methodical and structured to allow you to go on learning for a full day without overload. The training venue is superb and quiet enough (on the day I attended) to allow uninterrupted driving. Brilliant admin team too. Absolutely 5 Star!"
"Everything you read about these people is true and i cannot really add anything apart from clicking these five stars and to say they are truly incredibly knowledgeable, professional and nice. I did the Performance Driver Track day in my amazing six-month-old 911 GTS 4 and I now know so much more about my car and myself. I was in a group of six people all with different driving skill levels from the complete novice (me) to regular track day enthusiasts and the day was a journey of discovery for everyone. I am so pleased to have done it."
"First class performance car training day. Many thanks to Paul & your great team for a really enjoyable training day at Millbrook on Friday. I learnt a lot more about the capabilities of my F430 and found many new limits! The attention to detail in the delivery of the training was exceptional. I would recommend this to anyone with a performance car who wants to fully understand and enjoy their vehicle."
"An amazing day. If you drive you should go to CAT. If you have a performance car you MUST go to CAT. A day with CAT will transform your driving, you it be safer on the road in any situation and it will be the biggest performance upgrade your car will ever get. I learned so much in one day without any pressure, effort or stress. Colin's coaching is world class, he makes it simple / interesting to understand and easy to absorb / remember. The whole day and and everything leading up to it are well organised by the team. They REALLY care that you have a great day and TOTALLY deliver. You owe it to yourself to go."
"Absolutely Brilliant! The best advice I can give: believe every one of the glowing reviews on CAT! I approached CAT because I wanted to feel more comfortable with my newly-purchased BMW, the first rear-wheel drive car to be used for every-day driving after decades of FWD cars. I wanted to find out what the car's capabilities are, what it would feel like in extreme conditions, understand what it was telling me at the limits and, generally to get advice on my own technique. I wasn't a novice, having done plenty of track days and laps of the Nordschleife but I just knew that there's always plenty more to learn... A day's Performance Driver session met every one of my targets, and then more! Paul was a patient, logical and technical instructor who took time to explain what would happen in each manoeuvre and then fully debriefed that stage so that I not only knew what the car was doing but also understood what effect on the car my own actions were having. The proof of the pudding was in the final stage - setting consistent timed laps of the handling circuit. I'd worried a little about this all day as I'd have described my driving as enthusiastic but perhaps not consistent. The results were close to unbelievable to me! By remembering all that Paul had demonstrated and explained to me I surpassed my wildest dreams. Fantastic! As a result of this day, I now have more belief in my ability to read what my car's saying to me which brings confidence and relaxation. The car and I are now a team, rather than me just sitting there making it go down the road. I can highly recommend the whole CAT experience. Professional, friendly, patient, technical when required and not afraid to challenge when necessary. Oh, and the lunch is good too! I wish I could afford to go back every month..."
"Achieve your driving goals here! Can't ask for more than that! The entire experience was a positive and pleasant one. Everyone I met at CAT Driver Training contributed positively to the day, regardless of the role, so thank you to Jo, Lynne and of course, Colin! CAT have existing programmes for teaching anyone the fundamentals and advanced techniques of how to drive fast, but Colin can identify really quickly what you can and cannot do, and is quick to understand how to best use your time. I went in with my own unique set of requirements which slightly 'broke' the programme, but it was no problem at all and the most impressive thing was that I achieved my goals by the end of the day! I wanted to understand my car, be able to find and drive at the grip limit, and also understand how to be a faster and better driver. A lot to fit into a day, but Colin managed it in the most efficient way possible, and we achieved them all! Colin has great insights into vehicle dynamics, as well as the human machine behind the wheel. He understands why we sometimes don't function as optimally as we would like! His ability to listen to you, translate your input and isolate what is not working with your current technique helps focus the day on exactly what needs attention. This focus, along with Colin's 'feeling' of how the package of car and driver is behaving, makes him uniquely qualified to provide great direction and input to help you become the best driver possible. A lot of people talk about it, but very few can translate the inputs to a specific process for you to follow as a driver. The process is all about starting with foundations and building on them. It doesn't always seem to make sense, but trust the system - it all comes together in the end! The time is not cheap, but it will help you achieve your goals, so how do you put a price on that!? Thank you CAT Driver Training!!
"Best In Class Driver Training The training provided by Colin at CAT Driver training is superb. I am lucky enough to attended training days with Porsche, Lotus, Aston Martin and the day with a Colin at Millbrook has topped them all being informative, challenging, practical and above all delivered by a true Petrol Head. Thanks again and I will be back with the 911."
"Reminding how to drive fast A day with Colin on a 'One to One' basis is almost essential for anyone who lives on a small rock in the middle of the English Channel or lives in a city. We don't drive fast and don't get the opportunity to drive fast unless we are on a track. Colin spent the day reminding me how much fun it was to have 'fast feet' and to make the Tyres 'squeak' as they reach the sticky limit. I think I lost about 7kg in weight during the day as I was worked so hard but oh what a day. Thoroughly recommended to anyone who had a petrol head. Best bit was the 'Alpine Loop' at the end of the day. Full gas on the exit with all four squeaking. 👍😃"
"Excellent! Colin, Jo, Paul and the team are amazing, professional and have a unique ability to cover all areas of driving properly. My driving capability has been enhanced beyond measure. I highly recommend them and the CAT Advanced Driving Academy Programme. During the course it became clear to me that CAT Driving are one of the very few on the planet with such experience and capability. They have designed a brilliant dedicated package focused on working with you and delivered with an attentive caring personal touch."
"Paul was amazing: awesome teacher with a great brain. Made me realize my Mustang has actually way more grip and better and better handling than I thought. Top notch facilities in Millbrook. Totally worth it."