[Aditya]

Michelin has just completed 125 years in the tyre industry. To celebrate the milestone, the company organised a track day at the Yas Marina Circuit, Abu Dhabi. Journalists from India, Africa & the Middle East were invited, and I was one of the lucky chaps participating. Not only did I get to drive some exotic machines on the circuit, but I also got to enhance my knowledge about tyres. Here are two links to our earlier Michelin track day reports:

GTO's Report

Rehaan's Report



The founders; brothers André and Édouard Michelin, pictured on a wall showing the high points in the company's 125 year journey:


Éclair, the first car fitted with pneumatic tyres was introduced in 1895:


A cutaway of an early tyre:


Bibendum, the Michelin Man was born in 1898 - when the company was 9 years old:


Here's a look at the evolution of the Michelin Man:


The first Michelin Guide was published in 1900 (and yes, this is where 'Michelin Star Restaurants' got their name). More information:


The first Michelin Maps from 1910:


Michelin road signs in France from 1931:


After having looked around, we completed registration formalities and were divided into 4 teams of 4 each for the rest of the programme...

[Aditya]

Understanding Tyres

Expert Terry Khokhar walks us through the construction of a tyre:


Tyres are the only contact between a vehicle and the road. A tyre's footprint is no bigger than the size of a human hand for a car, two hands for a truck and barely a credit card for a motorcycle!

Although all tyres may look the same to the layman, it is an advanced product requiring more than 200 components to develop.

The tyre performs three basic functions:

1. Carries the weight (both static and dynamic) of the vehicle and its occupants
2. Guides the vehicle on the path decided by the driver
3. Transmits braking and acceleration torque to the tarmac

A tyre is made from 200 raw materials. Just the tyre rubber alone is made of four components:

• Rubber or elastomer - This is either natural (cultivated from trees) or synthetic (made from oil). It is shredded to facilitate the preparation of the rubber compound.
• Reinforcing fillers - Carbon black and silica reinforcing fillers are added to the elastomer to give it wear resistance.
• Plasticizers - Various plasticizers, including oils & resins, help to make the compounds uniform and facilitate extrusion.
• Chemical additives - These come in powder or granular form. Their formulation has to be accurate and regular. One of the additives is sulphur.

All of these components are mixed until perfectly uniform. The rubber compound is then conditioned for subsequent transformation.

In addition to the rubber, the tyre also has long metal cables and textile cords made of nylon, aramid (what most of us know as kevlar) etc. to withstand the stresses. The first such stress placed on the tyre is inflation itself. Once the various elements are prepared, they are transformed into a multitude of elements - flat products, shaped bead fillers, metal or textile wires, as well as bead wires.

Production then starts on a drum - a rotating cylinder with edges that can be brought together, and a centre that can be inflated. The first element to be laid on the drum is a thin airtight sheet of rubber which acts as an inner tube. It is then topped with a fabric ply (in the shape of a cord) encased in rubber. These cords form the radial carcass of the tyre. Extruding rubber bead fillers are installed on either side to accommodate the bead wires - inextensible metal loops used to clamp the tyre firmly against the wheel. The carcass ply is folded up over the bead wires to secure them in place. Other parts are then added. One of them is the sidewall, which is made of flexible yet tough rubber, designed to protect the tyre from side impact. After this, the centre of the drum is inflated to bring the two edges together and give the tyre its (nearly) final shape. Two plys - reinforced with metal wires placed crosswise to the carcass ply - are added to the tyre. The assembly of the components should be to tolerances of within 1/10th of a millimeter. Next, a fabric ply is laid down to encircle the tyre in the direction of rotation. This will prevent deformation due to centrifugal forces at high speeds. An extruding profile is laid down. This is the tread - the part in contact with the road surface. It completes the first stage in the construction of the tyre.

For the second stage, the tyre is transported to a curing mould where it gets its final shape and properties.

Here's a look at a cutaway:


Cutaway of a radial tyre showing the various layers:


Notice the cross-wise reinforcement here:


Ever wondered what the lettering on the sidewall is all about? Here's your answer:


Not all tyres are built the same, or use the same materials. Various applications require different tyres; e.g. a family sedan will need tyres with a higher aspect ratio compared to a sports car. The increased tyre height will give it cushioning, resulting in a more comfortable ride. A lower profile tyre will not give the same ride comfort, but is necessary for improving high speed handling. An SUV will need even more high profile tyres with a tougher construction to deal with the challenges of off-roading. The tread pattern varies according to the application as well.

Different tread patterns for different driving conditions:


Road safety was the theme of this event. Two critical tips:

• Choose tyres known for their quality - The elements & expertise used to manufacture a tyre must be consistently good to avoid dangerous surprises. Tyres from reputed manufacturers are likely to be safer than unknown brands.
• Maintain the right tyre pressure! Tyre pressures that are too low or too high are both dangerous. Ensure that your tyres are inflated at the pressures recommended by your car maker. The no. 1 reason for tyre blowouts is improper air pressure - related thread.

Grip, handling, comfort, endurance, longevity and fuel efficiency are all dependent on the right tyre pressure.

Effects of over-inflation:
The contact patch of the tyre decreases on over-inflation, affecting grip. Rolling resistance is reduced as well, thus the fuel efficiency improves. However, the ride will become harder and the tyres will wear out at the centre.

Effects of under-inflation:
The footprint of the car becomes wider. It also results in a softer ride. However, the sidewalls and shoulders of the tyre are prone to wearing out when under-inflated. The internal structure of the tyre is degraded, resulting in reduced tyre life. Handling, braking and fuel efficiency are negatively affected. Under-inflation is the No.1 cause of tyre bursts.

Four important tyre factors:


Geometry of the airbox:

• The height of the sidewall impacts the transversal and vertical rigidity of the tyre. It is also the determining factor that makes a tyre...a comfort or sport tyre.
• The outer diameter of the tyre impacts the length of the contact patch.
• As is obvious, the width of the tyre impacts the width of the contact patch.

Width of the rim:
This impacts the transversal and vertical rigidity of the tyre. It also influences the contact patch.

Operating conditions:
The vertical load and the inflation pressure determine how a vehicle will perform.

Tyre design:
The tyre structure, tread pattern and materials used impact the car's on-road behaviour.

[Aditya]

Tyre Safety (continued)

Further to the above listed safety points, we had another session conducted by Balaji Raghothaman:


The responsibility of tyre safety lies with four entities - the government, the tyre manufacturer, the distributor and the driver:

1. The government has to ensure that roads are built well and maintained properly. It has to set marked regulations and guidelines for road use and enforce the same.
2. The manufacturer must ensure that good quality materials are used, and tyres have a safe design. They have to ensure quality control in the manufacturing process as well.
3. The distributor has to see to it that he sells only certified and genuine products. Tyres need to be handled, stored and fitted in the right manner.
4. The driver should keep a check on the air pressure in the tyres. He should check the condition of the vehicle's tyres often, as well as ensure they are correctly balanced & aligned at set intervals.

Under-inflation can have some pretty bad effects on tyres. Among them is marbling. In this case, the tyre looks fine externally, but on the inside, a black marbling line appears on the sidewall. After prolonged use with low tyre pressures, a black line starts appearing on the external surface of the sidewall as well:




Puncture Repair:

When tubeless tyres suffer from punctures, there are two ways that they can be repaired.

1. Plug repair (the wrong method) - Also known as the temporary fix, this method takes just 5 minutes and is relatively cheap. Unfortunately, this method is largely prevalent in India. I didn't know it was wrong, and I'm sure it's the same for many among us:


2. Mushroom fix (the right method) - Also known as the permanent fix, this method takes about 20 minutes and is more expensive. A proper inspection of the tyre and buffing is involved:



Here's how the inside of the tyre would look after repairs. Plug repair on the left, mushroom on the right:


It is advisable to get your tyres repaired the mushroom way only. Tyres with any sort of damage to the sidewall must never be repaired. Additionally, sealants should be avoided. If the car remains parked for a long period, it can result in the liquid accumulating at the bottom. This can bring a loss of balance.

Points to remember:

• Be sure to check your tyre pressures at least once a month.
• Always inflate your tyres according to the manufacturer's recommendation.
• Fill air when the tyres are cool (e.g. tyres driven at slow speed for less than 3 kms).
• Never under-inflate or over-inflate them. If you need to remove some air from the tyres (e.g. driving on sand), be sure to fill air as soon as you return to regular tarmac.

The Petroleum Institute Solar Car

This is the first solar-powered car developed in the UAE. It's fully electric and is powered by the sun's energy only. It has a carbon fibre monocoque chassis and weighs just 150 kg (excluding the driver).

Three wheels shod with Michelin Solar 95/80 R16 tyres. Can attain a theoretical top speed of 150 km/h on a sunny day:


Most of the surface area is covered with solar panels:


A closer look at the cockpit. Most of the car's controls are mounted on the steering wheel. The power switch however, is placed to the right of the driver:


The car needs to minimize resistance as much as possible. Thin tyres mean a small contact area, reduced friction and less consumption of energy to move. Therefore, the car has two skinny tyres at the front...


... and one at the rear:




Small LED running light at the front, and a very slim aerodynamic profile:


A look at the specs:

[Aditya]

Driving on the Yas Marina Circuit

I have driven some really fast cars over the years. But, I had never driven a fast car on a track of the standards of the Yas Marina Circuit. Of course, we would be using only a part of the actual Formula One track.

Here’s a look at the drool-worthy line up:


Before any of us got our hands on them, we were given a briefing on track etiquette. Additionally, each one of us was accompanied by an instructor. The instructors would give us a demo lap and then hand the car over to us for three laps. The first one would be an out lap, on which we could get familiar with the track and car. The second would be a fast lap and the third would be a slowing down lap, on which we allowed the car to cool down before handing it over to the next driver. While we were driving, the instructors would guide us with respect to braking points and racing lines.

In our previous Michelin track day reports, you've seen GTO and Rehaan clad in racing suits. Nothing like that here. You could wear anything that you would be comfortable in, closed shoes, and of course, one of these:


With the head gear in place, participants looked something like this:


Ferrari 458 Spider:
4.5L, V8
562 BHP, 540 Nm torque
0-100 in 3.4 seconds
Top whack - 320 km/h

The first car I got to drive was the Ferrari 458 Spider. Driving any Ferrari is a special experience; on the race track, it makes for the stuff of dreams. The 458 was an absolute dream at Yas Marina! This was my first time on the circuit, so I kept the car in automatic mode. The out lap was very much a learning experience with my instructor telling me where I should go fast, where I should slow down and what lines to take. As we neared the end of the first lap and approached the start finish straight, he urged me to floor the accelerator. Pin the magic pedal down and the 562 horses are unleashed ferociously, with absolutely neck snapping acceleration. The engine is relentless, and its 0 - 100 time is on par with Formula 1 cars of yesteryears! Oh, and the melody from the exhausts on this track....it is loud & it screams! With the V8 orchestra playing in perfect symphony, we raced down the track. Once we crossed 240 km/h, I stopped looking at the speedo. The transmission's upshifts are lightning fast. Coming to a corner, you get a good feel of how quick the steering is. It is just so unbelievably direct and precise. The Ferrari points exactly where you want it to. This is a purpose-built driving machine...a race car that also happens to be road legal. Add to that, the phenomenal grip and you get a car that devours chicanes effortlessly. The chassis exhibits immaculate poise and all that technology & gizmos ensure the car stays glued to the tarmac. On my fast lap, I was attacking the corners, but well within the car's limits, as it was my first time with the 458. Still, the Italian beast could do some serious speeds through the curves, always urging you to go faster, push harder. And the high-pitched wail....it's like a celebration of speed. I don't have any lap times to share, but the instructors were of the opinion that around the circuit, the 458 Spider was the fastest car of the lot.

In my opinion, the 458 is the best entry-level Ferrari since the 355:



The pipes that play the awesome music:


Red interiors are a love it or loathe it affair. I personally prefer black. The steering wheel also feels cluttered:



Porsche 911 Cabriolet:
3.4L, 6-cylinder
345 BHP, 390 Nm
0-100 in 5.0 seconds
Top whack - 286 km/h

Next up, the Porsche 911. Like a typical German, this car is fantastically built. Everything feels just awesome to touch and hold. The rear engine gives it great traction off the line which aids rapid acceleration. And the Porsche is not only about straight line performance. Old Porsche 911s used to be notorious for their rear heaviness when it came to corners. However, the past few avatars of the car have been much more idiot-friendly and this one is no different. I have to hand it to Porsche's engineers. The balance and handling is so good that the 911 is a joy to throw around in the corners. Even with just rear-wheel drive, never once did I feel that it would go out of control. The precise steering only adds to the experience. With every corner, my confidence grew and my speed increased. The 911 lacks the power of some of the other cars I drove that day. Yet, it more than makes up for it in the corners. Unless one drives like an absolute maniac, I don't think he will run into any trouble with this car. I have loved the 911 since as long as I can remember, and this latest incarnation of the legend hasn't disappointed. It remains the definitive sports car for me.

The familiar face of the 911. Many would call Porsche's designers lazy, but for fans, this is a timeless classic:




The 911 excels on the track, whether it is going straight or tackling corners:


Michelin Pilot Sport Cup 2 tyres on 20" rims:


Audi R8 Spyder:
5.2L, V10
518 BHP, 530 Nm
0-100 in 4.1 seconds
Top whack - 312 km/h

The Audi R8 was my next ride. I’ve never been a fan of the car, but those few laps on the track dramatically changed my perception about the R8. It has all the ingredients that are necessary to make a super car – good looks, a healthy dose of BHP, two seats and a rather rubbish storage area. However, the best thing about the R8 is the ease with which one can drive it. It is just so controllable! You could be forgiven if you thought you were driving an A6; when you give it the loud pedal though, it is capable of delivering devastating performance. Down the straight, it may not be quite as urgent as the 458, but it is still damn quick. Approach a corner and the R8 shines. The Quattro system gives it a safe and civilised feel, while the tyres grip viciously. Through the "S"es, the car is extremely quick. The R8 instills immense confidence in the driver, and even a novice will be tempted to push the car to its limits. I was entering corners hard and exiting fast. Eventually, the R8 will understeer, but I barely reached that stage. Quick, safe and extremely user-friendly, this is easily the super car I’d recommend to a prospective buyer from India.

The R8 lacks a truly exotic badge, albeit all things considered, it is probably the supercar most people will want to buy:


I feel the R8 isn't as dramatic to look at as some other supercars:



On the track, the R8 is the most user-friendly supercar around. It urges the driver to push harder:


Toyota GT86:
2.0L, 4-cylinder
197 BHP, 205 Nm
0-100 in 7.6 seconds
Top whack 230 km/h

After the R8, I stepped into the Toyota GT86. This was the only hardtop and the least powerful car of the lot. The relative lack of power was easily evident. On parts of the track where I was comfortably doing more than 250 km/h in other cars, this one was barely managing 200. Even the steering isn't as quick. But then, the GT86 was never meant to compete with the others. For those on a budget, the Toyota is a joy! The car's handling is fantastic and this means the driver can have a great time around the bends. Because it doesn't have too much power, you get the feeling that you are constantly on the limit. There's a certain appeal in pushing a not-so-powerful car to the edge. On a winding country road, I’m sure the GT86 will be a gem to drive. This was also the easiest car to get into and out of, and since it’s a Toyota, it will probably be very reliable as well.

The only hardtop of the bunch:


The GT86 has typical GT styling:


Lacks the power to compete with supercars on track. That said, in the real world, it should be more than enough. Handles beautifully too:


While the rest of the cars were running on Pilot Sports, the less powerful GT86 got tyres from the Primacy range:


Mercedes-Benz SLS AMG GT Roadster:
6.2L, V8
583 BHP, 650 Nm
0-100 in 3.8 seconds
Top whack - 317 km/h

As my long-time favourite, I’ve been fond of the German’s looks, power and sound. On the straights, this car is a monster! It could close in on any of the others. In fact, on one instance, I got a little competitive and the instructor asked me to slow down. However, once you get past the tremendous power & speed and approach a corner, the car turns out to be a bit of a disappointment. You always get the feeling that the car has too much power for its own good. All the cars I had driven before this were very good in the bends. Comparatively, the Merc didn't inspire much confidence. The steering too is not as precise as say the 458. No one had to ask me to go slow on the bends, as I tip-toed the car around. My mirrors were soon full of the R8 and 911. They rapidly reined me in and walked past without any effort - provided we weren't on a straight where I'd thunder past them. The SLS AMG GT feels more like a muscle car than a supercar. It sounds like one too. I can't comment on the ride as all the driving was done on a smooth track, but I get the feeling this car will make for a good tourer. It will appeal to those looking for a comfortable supercar to cover great distances at high speeds, rather than attack the track with.

The SLS AMG GT is a handsome looking brute:


The driver sits way back - almost on the rear axle. The long bonnet stretches out in front:


The rear is somewhat bland in this company:


The most powerful car was probably the quickest tyre destroyer as well:


In a straight line, the SLS AMG GT was the fastest car of the lot. Not so brilliant in the corners:


Chevrolet Corvette Stingray:
6.2L, V8
455 BHP, 624 Nm
0-100 in ~4.0 seconds

The last car I drove was the Chevrolet Corvette Stingray. Looks are subjective, and to me, this was the best looking of the bunch. It has more than enough power to storm down the straights and before you know it, you will be doing some pretty insane speeds. What is surprising is the way the car handles. There is none of the dipping and wallowing that American cars are infamous for. The chassis is stiff and the handling is sharp. The Corvette can romp through corners without any fuss. Like some of the other cars I drove that day, the Corvette is very manageable and will ask to be driven faster. The sound from the four exhaust pipes is good enough to turn heads as well. On the downshift, it blips the throttle and the musical experience is taken to a different level. Not only is the American car fun to drive, but it also has nice interiors. I love the way the dashboard curves around the driver. Together with the high centre console, it gives a good cosseted feel. This car also has a head-up display, which means that the driver doesn't have to take his eyes off the road to look at the instrument cluster. The only thing I didn't like about the Corvette was that the brake pedal travels a longer distance before the brakes actually bite. For something so powerful, I would have liked a more immediate braking action, especially while driving on a track. Still, I was rather impressed by the Corvette. It is a thoroughly VFM car.




With the sort of performance on offer, this is what most other cars on the road are going to be seeing:




I'm not a fan of the red highlights, but I love how the dashboard curves to cosset the driver. Gives a cockpit-like feeling:

[Aditya]

For the next part of the track day, we were taken to another part of the Yas Marina Circuit complex. Here, we were given a demonstration of how a car behaves through a slalom course with the proper tyre pressures (33 PSI) and with under-inflated tyres (17 PSI).

The cars chosen for this job were a couple of Toyota Camrys.

As usual, before we hit the course, a small briefing! We were asked to build up sufficient speed, without which it wouldn't be easy to tell the difference:


A test-driver gave us a demo lap before handing over the wheel. The white car with tyres properly inflated went first:


The tyres were squealing while tackling the slalom, but the car stayed on course without much effort:


The Camry is far from being the best handling car in the world; at least with the tyres inflated properly, it handled predictably:



Once past the slalom, we had to accelerate hard:


With properly inflated tyres, the car managed this easily:


The end point was this “box” where we had to screech to a halt. This Camry had no trouble managing it:


Next up, the silver car with under-inflated tyres:


Immediately, the sheer effort needed to keep the car on course was evident. The steering became heavy and the car had to be wrestled through the slalom:



At the hairpin bend, if one doesn't concentrate hard, it's easy to run wide:


Under hard cornering, there is also a risk of an under-inflated tyre coming off the rim:


The car's overall acceleration is slower too:


Unevenly inflated tyres cause the car to pull to one side, making it necessary to hold the steering wheel firmly all the time:


Even when it comes to braking hard, one has to hold the steering really tight to keep the car straight:


The final activity of the track day involved braking from speeds of 60 km/h vs 100 km/h. Most of us would think that a difference of 40 km/h won't alter the outcome too drastically. You’ll be shocked to learn how wrong you are. Oh yes, this activity was conducted with a car with properly inflated tyres.

The blue board marked the set off point:


The yellow board marked the braking point. The car had to be travelling at 60 km/h when the brakes were slammed on:


There was another blue marker at the far end of the track. For the car to reach 100 km/h, this was the set off point:


The braking point was the same in both cases. The difference in stopping distance between the two speeds was a whopping 20 metres! That's a lot of distance:


That concluded the track activities for the day, all of which were very well-conducted and served as great learning experiences for me.

[Aditya]

I'll leave you with some shots of the stunning Yas Marina Circuit:

View from the pitlane. That's the box from where the chequered flag is waved:


The track tries to replicate the Monaco feel by adding a bay where yachts can be docked:



Beyond the bay is the main straight, on which the V8 / V10 / V12 cars scream their guts out:


Stick to the left and turn right to hit the apex, before a sharp left:


Part of the track runs underneath the hotel in which we were staying. Guests can sit in this balcony of the open-air restaurant and enjoy the proceedings:




Disclaimer: Michelin invited Team-BHP for the track day @ Yas Marina. They covered all the travel expenses for this driving event.

[GTO]

Thread moved from the Assembly Line to the Tyre Section. Thanks for sharing!

[Rehaan]

Addy you lucky fella... That's quite a super-car line-up!

I was not familiar with the "marbling line" seen on tyres that have been run under-inflated for a long amount of time. Learned something new there, and it's quite different from the "marbling of tyres" in F1 etc - which refers to the small balls of rubber left on the track from tyre-wear.

[ajmat]

Nice crisp review. The man in the Bibendum costume must be dying in the heat

[S2!!!]

A very informative report. I'm sooo jealous of you right now for having driven some of the most desirable supercars in the world . And again you've gone for another supercar drive

Originally Posted by Aditya

1. Plug repair (the wrong method) - Also known as the temporary fix, this method takes just 5 minutes and is relatively cheap. Unfortunately, this method is largely prevalent in India. I didn't know it was wrong, and I'm sure it's the same for many among us:

Could you please explain as to why is this a wrong method?

[agnimidhun]

Thanks a lot Aditya for sharing this ! Very informative. The Mushroom method seems pretty close to how a tube tyre would be repaired. I was not aware of the Mushroom method for tubeless tyres too.

Originally Posted by S2!!!

Could you please explain as to why is this a wrong method?

I would like to know the same ! I have so many punctures on my Fabia's tyres and after reading your post I am wondering what will happen to the tyres now. At one time I had got 17 punctures across all the four tyres fixed using the Plug method.

On another note, I usually find puncture kits using the Plug method only. I think it is good business idea to have mushroom patches or rather a patch for the whole of the inner tyre for people with lot of punctures

Thanks!
Midhun

[naveenroy]

Wow, so we've been doing the plugging wrong! Mushroom - never even heard of that here eh? Maybe it is better cause it provides more surface area for the fix rather than the plug repair.

Cars are really droolworthy.

[Rehaan]

Why to avoid plug-only repair for tyres:

Simply put, a plug is a quick and temporary way to fix a tyre.

A quick recap on how tyres are plugged:
1) Remove nail / object causing the puncture
2) Ream the whole to make it a uniform size & shape
3) Push the plug in with the provided tool

Sometimes this can all be done without even having to take the wheel off the car. Very convenient, but remember - it's done as a temporary solution!


What's wrong with the plug?

• It's just squeezed in there. Sure, it's a bit sticky, and sometimes it'll stay in there for the life of the tyre. However, there's a constant air pressure trying to force it out.
• If/when a plug comes loose, you'll have a very sudden loss of pressure (compared to most punctures).
• Plugs can be done without removing the tyre from the rim. This means that the tyre isn't properly inspected at the time of repair. (A lot of times damage from driving on a flat tyre can only be seen on the inside).

What's the correct way?

The correct way is actually a plug AND patch approach!

What Michelin has shows is not just a 'patch'. Look closely, it is a 'Plug AND Patch':


The patch has two advantages:

1) Unlike the plug which is being forced out by the tyre's high air pressure, the patch uses this to stick itself to the inside of the tyre.
2) The patch vulcanizes itself to the rubber of the tyre. These can either be self-vulcanizing patches; which use the heat from when the tyre is driven, or a hot-patch, that requires some heat & pressure from an external source after it has been applied.

It's also worth noting that plugs are banned by the authorities in a lot of countries.

Another thing to remember:

Only repair tyres when the puncture is on the tread section, and the hole is not bigger than a 1/4". Never attempt to repair or re-use a tyre with a damaged side-wall.

Patching is a longer, slower, more expensive job - but you get what you pay for. Don't risk a life just to save a few bucks.

[D33-PAC]

Dumb question for all the technical experts out there -

for economy cars such as the Corolla price matters for potential tire purchasers, but for high end car owners, what is the real selling point to say, an owner of an SLS AMG, or a Ferrari California. Price is certainly no issue for them, so why are there so many brands available for a tire, what difference does using a Michelin or a Bridgestone on a Ferrari California make - does it even matter what tire you use at that point (won't they all give uniform performance ) ?

[rlakhanpal]

Foremost, you are one lucky fella!

On a serious note though,

Originally Posted by Rehaan

Why to avoid plug-only repair for tyres:

What Michelin has shows is not just a 'patch'. Look closely, it is a 'Plug AND Patch':
....
Patching is a longer, slower, more expensive job - but you get what you pay for. Don't risk a life just to save a few bucks.

Does Michelin ask its Indian dealers to ensure this while repairing Michelin tyres, or at least recommend this to the customers who come for puncture repairs?

If not, all this is useless! Bookish, "ideal" scenario but no leadership in ensuring safety for its own customers.