Why do we have to have low profile tyres to look "sporty"?

[Kawasicki]

ddom said:

Kawasicki said:

Nope. That’s not even remotely logical.

Really. Are you honestly trying to say that an F1 wheel is subject to cost constraints over performance?

One constraint isn’t over the other. They are simultaneous constraints.

[Kawasicki]

ddom said:

Kawasicki said:

Yes, and everyone was telling me that because they were lighter they would reduce unsprung weight and that the car would handle better with them.

All wheels are compromised by cost constraints.

For a certain cost I’ll take a medium weight wheel with excellent stiffness over a super duper light wheel with average stiffness. Unsprung weight is just one part of the compromise.

Some wheels are compromised by cost constraints

Perfection is just a simple equation of time and money.

Can you point me to an example of a wheel not compromised by cost constraints?

[A1VDY]

Hagus said:

Why do people even want to look sporty.....?

This^
It suits a certain demographic though. With a 70mph speed limit {ever decreasing) clogged potholed roads its all pretty pointless.
The nerdy goofy type ph'ers with milk bottled lensed glasses who spout 'heel & toeing,' making progress ect ect will totally disagree though, they need the ultra low profile tyres on their white knuckle 'hoon' to Tesco's at 40mph...

[Kawasicki]

A1VDY said:

This^
It suits a certain demographic though. With a 70mph speed limit {ever decreasing) clogged potholed roads its all pretty pointless.
The nerdy goofy type ph'ers with milk bottled lensed glasses who spout 'heel & toeing,' making progress ect ect will totally disagree though, they need the ultra low profile tyres on their white knuckle 'hoon' to Tesco's at 40mph...

You can’t really post stuff like this without appearing to be even more of a nerdy goofy type milk bottle lens glasses wearing type than those you’re belittling.

People like sporty looking cars because, I expect, they think they look better.

[FNG]

A1VDY said:

This^
It suits a certain demographic though. With a 70mph speed limit {ever decreasing) clogged potholed roads its all pretty pointless.
The nerdy goofy type ph'ers with milk bottled lensed glasses who spout 'heel & toeing,' making progress ect ect will totally disagree though, they need the ultra low profile tyres on their white knuckle 'hoon' to Tesco's at 40mph...

Worst “I wear contact lenses” post evah

[MC Bodge]

A1VDY said:

This^
It suits a certain demographic though. With a 70mph speed limit {ever decreasing) clogged potholed roads its all pretty pointless.
The nerdy goofy type ph'ers with milk bottled lensed glasses who spout 'heel & toeing,' making progress ect ect will totally disagree though, they need the ultra low profile tyres on their white knuckle 'hoon' to Tesco's at 40mph...

To be honest, I'm one of those heel & toe, balanced car types, but I'm not interested in "sporty" looking or big wheels at all.

[AW111]

MC Bodge said:

A1VDY said:

This^
It suits a certain demographic though. With a 70mph speed limit {ever decreasing) clogged potholed roads its all pretty pointless.
The nerdy goofy type ph'ers with milk bottled lensed glasses who spout 'heel & toeing,' making progress ect ect will totally disagree though, they need the ultra low profile tyres on their white knuckle 'hoon' to Tesco's at 40mph...

To be honest, I'm one of those heel & toe, balanced car types, but I'm not interested in "sporty" looking or big wheels at all.

I'm one of those types, which is why I did some research as to the best all-round wheel & tyre size.
Which is not the biggest, lowest profile that fits.

[Kawasicki]

AW111 said:

I'm one of those types, which is why I did some research as to the best all-round wheel & tyre size.
Which is not the biggest, lowest profile that fits.

It´s also not the highest profile tyre that fits.

The best tyre profile is the right one for the application. This thread is an exercise in the obvious.

[nickfrog]

Kawasicki said:

The best tyre profile is the right one for the application.

Thank you. The entrenched and polarised views expressed in this thread are tiresome. Add very limited understanding of engineering and you end up with a total mess of a conversation. Light, stiff and cheap: peak 2 of them as you can't have 3. I am convinced this is very easy to grasp for most people who understand that the metrics are relative.

I want my wheels as small as possible and my tyre profile as high as possible but ONLY if my objectives are reached: big enough discs and good enough response even at the detriment of comfort and weight, that's my application and my compromise, irrespective of fashion. I couldn't give a toss if the next guy buys for fashion, why would anyone care and draw ridiculous conclusions and sweeping generalisations?

Edited by nickfrog on Thursday 7th January 11:08

[thatdude]

one thing I dont like about the civic type r is the stupid low-profile of the tyre. People elsewhere have bought 18 inch wheels and fitted a higher profile tyre - looks much better, and is reported to be more comfortable ride.

[havoc]

Kawasicki said:

Nah, lighter wheels handle worse, due to a lack of stiffness.

Having read the comments above, I still disagree.

IF you're talking about the same construction material, then you're potentially right, although there would still be a balancing act between the benefits of the lower unsprung weight and the costs of a less-stiff wheel.

But if you're comparing a high-volume cast or semi-forged wheel vs a forged wheel with the right structural design (not that difficult), then you're wholly wrong. There are plenty of cars out there running lightweight alloys, with all the commensurate benefits.


...and can I politely suggest that the kinematic load would have to be exceptionally high to (temporarily?) deform a wheel enough for it to affect the handling (i.e. the wheel deformation is a bigger problem than the much greater tyre deformation). Not sure where on the public highway you're going to encounter that...

[NGRhodes]

Kawasicki said:

AW111 said:

I'm one of those types, which is why I did some research as to the best all-round wheel & tyre size.
Which is not the biggest, lowest profile that fits.

It´s also not the highest profile tyre that fits.

The best tyre profile is the right one for the application. This thread is an exercise in the obvious.

Or the best overall compromise.

[NGRhodes]

ddom said:

Kawasicki said:

Because there is less material to resist bending/deflection.

Engineering is about compromises.

What do you mean by “relative strength“?

Forged wheels, Magnesium wheels, carbon wheels. How is unsprung weight ever a benefit to handling?

Lower centripetal forces against the springs/dampers which means the suspension can work more responsively (lower inertia) allowing the wheel to track the surface of the road more evenly and maintain traction.

Edited by NGRhodes on Thursday 7th January 12:06

[Kawasicki]

havoc said:

Kawasicki said:

Nah, lighter wheels handle worse, due to a lack of stiffness.

Having read the comments above, I still disagree.

IF you're talking about the same construction material, then you're potentially right, although there would still be a balancing act between the benefits of the lower unsprung weight and the costs of a less-stiff wheel.

But if you're comparing a high-volume cast or semi-forged wheel vs a forged wheel with the right structural design (not that difficult), then you're wholly wrong. There are plenty of cars out there running lightweight alloys, with all the commensurate benefits.


...and can I politely suggest that the kinematic load would have to be exceptionally high to (temporarily?) deform a wheel enough for it to affect the handling (i.e. the wheel deformation is a bigger problem than the much greater tyre deformation). Not sure where on the public highway you're going to encounter that...

My comment that lighter wheels handle worse due to a lack of stiffness was made to provoke debate. It highlights that there is always a compromise between weight and stiffness. Even the best grade of carbon wheel will be made stiffer with additional carbon. How stiff is stiff enough is the question? How light is light enough is another one? Should you spend x amount making the wheel lighter, or the same amount making it stiffer... or should you spend the money on a better/stiffer wheel bearing, or spend the money on certain body stiffness characteristics.

You don’t need to politely suggest (though it’s kind of you) that you find my statement about wheel stiffness being important for handling in typical customer usage questionable. I agree it seems counterintuitive. I’m quite comfortable about being asked how it could possibly be the case in a room full of not polite engineers. Wheel stiffness weirdly has an influence on very low lateral load characteristics. Steering from left to right with a peak of 0.2g is enough to see it, multiple test drivers report in a blind test the same feedback.

There are more and more people aware of these characteristics being important. Some (massively successful) companies have already got targets for various measures of wheel stiffness precisely because it influences the typical customer experience.

[NGRhodes]

Kawasicki said:

Nah, lighter wheels handle worse, due to a lack of stiffness.

Possibly a case at the extreme with light steel wheels, but I would not of thought so with alloy wheels.
I thought the biggest issue with mass produced light alloy wheels (strong enough not to flex is that they are prone to cracking.
The main ways to increase resistance to cracking are to use more material or better quality alloys, or better manufacturing techniques such as flow formed or forged instead of cheapest option - cast), each option has its advantages and limitations.
Please explain if I am wrong.

Edited by NGRhodes on Thursday 7th January 12:14

[Kawasicki]

nickfrog said:

Kawasicki said:

The best tyre profile is the right one for the application.

Thank you. The entrenched and polarised views expressed in this thread are tiresome. Add very limited understanding of engineering and you end up with a total mess of a conversation. Light, stiff and cheap: peak 2 of them as you can't have 3. I am convinced this is very easy to grasp for most people who understand that the metrics are relative.

I want my wheels as small as possible and my tyre profile as high as possible but ONLY if my objectives are reached: big enough discs and good enough response even at the detriment of comfort and weight, that's my application and my compromise, irrespective of fashion. I couldn't give a toss if the next guy buys for fashion, why would anyone care and draw ridiculous conclusions and sweeping generalisations?

Edited by nickfrog on Thursday 7th January 11:08

Succinctly put.

Can I add toughness/robustness to your light, stiff and cheap though?

[nickfrog]

Kawasicki said:

Succinctly put.

Can I add toughness/robustness to your light, stiff and cheap though?

Of course you can as "stiff" only partially covers it.

[Kawasicki]

NGRhodes said:

Kawasicki said:

Nah, lighter wheels handle worse, due to a lack of stiffness.

Possibly a case at the extreme with light steel wheels, but I would not of thought so with alloy wheels.
I thought the biggest issue with mass produced light alloy wheels (strong enough not to flex is that they are prone to cracking.
The main ways to increase resistance to cracking are to use more material or better quality alloys, or better manufacturing techniques such as flow formed or forged instead of cheapest option - cast), each option has its advantages and limitations.
Please explain if I am wrong.

Edited by NGRhodes on Thursday 7th January 12:14

Every wheel flexes under load. How much flex is acceptable?

[AW111]

NGRhodes said:

Kawasicki said:

AW111 said:

I'm one of those types, which is why I did some research as to the best all-round wheel & tyre size.
Which is not the biggest, lowest profile that fits.

It´s also not the highest profile tyre that fits.

The best tyre profile is the right one for the application. This thread is an exercise in the obvious.

Or the best overall compromise.

Precisely.

Which is why I have different sizes & profiles on my 2 different cars.

[Glosphil]

I don't buy new cars - usually 12-18 months old. It is difficult to find a well equipped version of a car where the optional bigger diameter wheels had not been specified by the original owner. Have changed 225/40-18 to 225/45-17 or 205/55-16. All have very close to the same rolling circumference.
It least my winter wheels are 1" or 2" smaller diameter with higher profile tyres.
Even my wife's 2010 Clio has 195/50-16 tyre. On a 100hp 1070kg car!