23 replies to this topic

[libano]

Tyre wear seems to be a topic popping up very frequently, especially at the start of a season. What are the factors that cause one car to have more tyre wear than another, apart from the obvious (balance, downforce levels)?

Cheers!

[Andromeda]

Tyre wear seems to be a topic popping up very frequently, especially at the start of a season. What are the factors that cause one car to have more tyre wear than another, apart from the obvious (balance, downforce levels)?

Cheers!

Weather and driving style are another 2 big factors. Tyres will suffer degradation much quicker in warmer weather and while in cooler weather they last longer depending on how the car is setup of course as each car is different as for driving style its how aggressive and how late and hard you are braking can cause massive tyre wear as seen many times from Hamiltons driving style compared to Buttons.

Edited by Andromeda, 19 March 2012 - 17:46.

[flyer121]

Car

[654321]

not ideal ballast positionning/suspension set up,not enough downforce(fundamental),driver pushing too much,wheather....

Edited by 654321, 19 March 2012 - 17:58.

[steferrari]

http://youtu.be/GHUaoxe3Lb4?hd=1

[sharo]

I guess the main reason is friction.
AFAIK cold tyres grain, overheated blister.

[miniq]

Loss of traction(spinning the wheels). overheating. Flatspotting.

Edited by miniq, 19 March 2012 - 19:17.

[repete]

Lewis Hamilton

[pingu666]

physical wear thats different from car to car or drivers would be the amount of scrub or sliding of the tyres, the track is acting like sandpaper, basicaly. thing is some amount of sliding or slip is good, gives you peak grip.

degredation is how much the tyre loses performance, which can be unrelated to wear.

rears seem to be weaker on pirellis, in some cars/racetrack/series combinations its the fronts

[HoldenRT]

Friction and heat (caused by the friction).

Tyres have an operating window.. an ideal range where they work best and slide the least while offering the most amount of grip. Go outside of this window and the tyres will slide too much.. sliding = excess friction and wear. Go too much over this range (overheat) and they can blister as well.

It's a downward spiral anyway because anytime they wear they will slide more so the driving has to be adjusted accordingly. The worse and worse it gets the more it becomes like tippy toeing on ice. Some drivers have this ability better then others and it's a completely different discipline compared to 1 lap pace. The drivers try to get into a rhythm so that they know better what to expect.. so that it becomes easier to toe the line.. of too much or not enough sliding. No sliding at all means not close enough to the limit. The tyres are always sliding, it's just a matter of finding the ideal amount so to keep tyres in their optimum temp window.

Car setup also plays a role.. and the cars characteristics, the drivers style and preference and the cars setup all have to work hand in hand.

One other thing.. softer compounds have a higher optimum window.. harder compounds on a coldish track, can actually require an aggressive style in order to get the tyres working in their optimum range. And as the track conditions change (rubber levels on the track, or track temperatures) so does the driving have to be adjusted.

Motor racing is awesome.

[BigCHrome]

Suspension settings.
Harder springs = more tire wear; stiffer ARB = more tire wear.

[F1Champion]

Its an interesting question that puzzles me because the Mercedes has good downforce which you would normally say is a major factor in tyre wear, the more you have generally the less sliding and less wear, but then you have a car like Ferrari which looked to handle worse and slides more but had better tyre wear. I think with Mercedes case, the tyres are switched on immediately so the car looks to get them immediately to operating temps, however in the race it could be overheating them.

Hard to think if suspension and ballast can easily solve their problems.

Edited by F1Champion, 20 March 2012 - 19:05.

[F1Champion]

Suspension settings.
Harder springs = more tire wear; stiffer ARB = more tire wear.

But don't McLaren run stiff front end, yet have very good tyre wear.

[g1n]

But don't McLaren run stiff front end, yet have very good tyre wear.

Exactly, the other guy that you quoted probably plays too many racing sims, which simplify reality.

[911]

Tyre wear seems to be a topic popping up very frequently, especially at the start of a season. What are the factors that cause one car to have more tyre wear than another, apart from the obvious (balance, downforce levels)?

Cheers!

Brief answer: Incorrect suspension/chassis setup and/or over zealous driving style

[BigCHrome]

But don't McLaren run stiff front end, yet have very good tyre wear.

These tires are the same compound front to rear, so the rears wear out a lot quicker than the fronts (since they are driven by the engine). Front tire wear is very rarely an issue.

[IceSkyrim]

Lewis Hamilton

[PassWind]

The blistering is caused by uneven heating of the tyre, if the outside heats too fast, while the core remains cool the compound can delaminate internally and its outward appearance is blisters, as it's not universal across the tread. If the compound is very sensitive to is sometimes cool track conditions can be the main contributor, in other words dropping a preheated tire under the temp needed to ensure delamination doesn't happen.

Sometimes it's driving technique, however all drivers strive to brings their tires in without this happening while going as quick as possible.

Tire wear, is just friction related.

[PretentiousBread]

Mark Hughes wrote a superb article on 'The black art of tyres' for Autosport's 2011 season preview. I dug it up and thought i'd share:

The black art of F1 tyres


Why is tyre behaviour difficult to grasp – even in Formula 1? Mark Hughes dons his white coat…


The tyre is the most powerful performance generator on a racing car. It’s way more important than – though inextricably linked to – aerodynamics. A 10 per cent increase in downforce with no drag penalty would typically give 0.3s. A 10 per cent hike in tyre grip would give more like 2s.

Yet in an age when F1 teams can simulate the mechanisms of airflow, suspension kinematics, cooling, brake wear and dynamic stresses on any part of the car, tyre performance remains part science/part black art.

The tyre engineers would disagree with that, tell you that just because the teams don’t always fully understand the bewildering complexity of tyre behaviour it doesn’t mean that they don’t. But even they will admit that tyre performance on the day is not fully under their control.

To begin to comprehend the various tyre-related anomalies – cars unable to ‘switch on’ the tyres, drivers’ styles being suited/unsuited to particular tyres, how sliding can sometimes overheat the tyre yet at other times cause it to run too cold etc – it’s as well to study how a tyre is constructed.

Starting from the inside and working out, there is first the basic carcass extruded from a lump of mixed rubber (natural and synthetic), carbon, sulphur and other chemical ingredients. This is rolled out into a flat length before being formed into a circle of the required mass for the eventual diameter/width. The tyre cord – a belt of rubber embedded with plies of Kevlar – surrounds the carcass. The carcass and cord are then encased by a steel belt and the whole thing is then further encased – at the sides by the sidewalls and on top by the tread. The tyre is then vulcanised – essentially cooked – in the tyre shape determined by a mould. This process merges the natural rubber with the various chemicals at molecular level, creating elasticity.

Some of the Kevlar plies within the cord run circumferentially around the tyre. Others run radially across the tyre. The former keep the tyre from expanding or contracting as the tyre is braked or accelerated and play a crucial part in the car’s springing, braking and traction. The latter determine stability and directional response.

A tyre utilises two mechanisms to create grip: mechanical and chemical. Mechanical grip is generated by the unsymmetrical way the tread drapes itself over track-surface irregularities. There is a compression effect as it pushes against the grain of the track but because of its elasticity it reacts by trying to pull itself back to symmetry, creating a force in the opposite direction to the cornering load and thereby generating grip. Chemical grip is to do with the way the rubber interacts with the track surface at a molecular level – how the two materials ‘stick’ to each other, in effect.

The energy put into the tyre by the various loads of cornering, braking and accelerating is absorbed by the tyre and as it bends and rebounds it creates heat. This breaks down the rubber compound, increasing the chemical grip, and this process is termed hysteresis. A softer compound can generate more hysteresis than a harder one – so long as it reaches operating equilibrium. The frequency of the loads may overwhelm it, prevent the tread from properly pulling itself back to oppose the cornering load. This is when a compound is too soft for the track – or the car, or driver. Another possibility is that the tread fails to reach its correct operating temperature of 90-100C.

The interaction between the construction’s mechanical grip and the compound’s chemical grip determines the temperature at which the tyre runs. If it runs too cool, the tread remains stiff and brittle, the chemical bonding doesn’t occur and grip remains low. This can become a feedback loop – because the grip remains low, the tyre remains to cool and the grip therefore remains low. Once it passes a certain temperature threshold however, the process of chemical bonding will begin and the grip will increase hugely. This is when the tyre ‘switches on’.

Depending upon the conditions prevailing – the car’s weight, its static and dynamic weight distribution, its suspension kinematics, the driver’s style, the track’s layout and surface, the track temperature – there are many reasons why a tyre works well or not. These independent parameters cannot all be controlled at the same time and that’s why even within a control-tyre formula there are still big variations.

So it can be that Jenson Button, say, is driving just the right side of overwhelming the tyre. He therefore can get it to its operating temperature and it works beautifully. On that same day Lewis Hamilton (with the same car and tyre) may induce more initial load into the tyre, which overwhelms the compound, which cannot therefore reach equilibrium and therefore remains stiff, cool and gripless. On another day, that may not be the dominant mechanism and the tyre may need to be pushed harder in order to switch it on. Hamilton may reach that threshold while Button does not.

On a car that, say, works its front tyres very lightly it can be difficult getting them up to temperature in time for one timed lap. In which case a driver who initially just coaxes grip from them, doesn’t overwhelm them initially and just allows the grip to buld until they have switched on, will do better than the driver who reacts to the cool tyre by throwing it at the corner. In this way he might actually overheat the surface of the tyre while still having the rest of it too cool and brittle because not enough g-loadings have gone through it.

A stiff construction will limit the tread’s movement – which on a day when the compound is marginally soft for conditions would be good. It would work to prevent the tread overheating. With a compound that was on the verge of being too hard, a stiff construction would be bad – because it would prevent the rubber from generating the correct temperature. A bit of cloud cover would change which of the scenarios applies – and which drivers or cars that best suits.

This is far from a comprehensive explanation of tyre behaviour, but hopefully enough to give some insight into why they can be so baffling even for F1’s brightest minds.

[Bloggsworth]

Transitioning from static to dynamic friction and staying in that condition - The more & faster you slide the higher the rate of wear.

[jamiegc]

But don't McLaren run stiff front end, yet have very good tyre wear.

Not in Melbourne

[HoldenRT]

Suspension settings.
Harder springs = more tire wear; stiffer ARB = more tire wear.

To name just one of the thousand variables..

edit - And for the record.. I made this post before seeing the "probably just played too many racing sims, which simplify reality" comment.....

The truth is you won't find a good answer to this question on this forum.. as it's too complicated and this forum is generally for driver related fanboy discussions.

People aren't even good sim racers here..

Try http://www.f1technical.net/ on their forum for more indepth discussion.

Edited by HoldenRT, 22 March 2012 - 14:42.

[Kimiraikkonen]

Low Df, generates bad traction and more stree in tyres.

Driver skills too.

[HoldenRT]

The copy pasted article is correct.. all you have to read is the heading.. it's a "black art".