2022 Tyres Thread

[henry]

Not necessarily if they have higher mass and rotational inertia. That’s another thing that’s “worse” about the 18” solution. The actual mass will be higher reducing performance in all planes, and the referred mass, from the rotational inertia, will reduce performance in acceleration and braking.

If 13" tyres offer superior performance, why don't LMP1 competitors choose to use 13" wheels? Do the regulations mandate the use of 18" tyres?

Mandated, at least for LMP1.

In the days gone by 15” or 16” was popular, but obviously it depended on availability. By fixing sizes in regulations it makes it easier for competitors and manufacturers to tool up. For the competitors it provides a constraint which makes it easier to engineer. They hate change. Which is why they rejected the 2020 tyres.

[RedNEO]

Correct guess wins a prize

[Just_a_fan]

Williams unable/unwilling to send a mule car for the tyre tests. That's not going to help them one little bit next year, is it?

[RedNEO]

Williams unable/unwilling to send a mule car for the tyre tests. That's not going to help them one little bit next year, is it?

That’s why a partnership in 2022 with Alpine would be best for them.

[Peter1919]

Its a worrying sign that Williams still appear to be underfunded

[JordanMugen]

Tyres are provided by the nominated supplier. The tyre supplier doesn't want to make 13 inch tyres because they can't market them to boy/girl racers in their 2.0 litre hatchbacks.

They need to be at least 16" on my 2.0 litre hatchback to clear the brakes. I've got three sets:
16" (Mazda FD RX7)
17" (Mazda FD RX7)
18" (OEM Honda Civic Type R wheels)

Currently running the 17" wheels as they are nice lightweight forged wheels, as the 16" tyres had too much compliance in the sidewalls and made the handling a bit vague.

The 17" tyres seem to be OK as long as the tyre has reasonably stiff sidewalls like Potenzas. Pilot Sport 4 non-S were dreadfully floaty and had to be returned, and I worry that Eagle F1s would be nearly as bad (while I normally like Goodyear Eagle F1s, I've only driven them in 18" on the Civic or Megane, and unless you get the Eagle F1 Super Sport, they have a softer sidewall compared to Potenzas).

On the project car, a '93 Civic with the same 2.0 litre engine, it's running 15" wheels to clear 11" brakes, but they are fairly low-profile 15" tyres given the era of the car and the smaller overall tyres it runs compared to the later model Civic.

PS. I doubt the tyre suppliers have any issue making 13" tyres given they are still widely used in racing. Hankook were willing to make 13" on their F1 tender, Yokohama still make 13" for Super Formula, Kumho make 13" for F3000 type cars, as do Avon Cooper, Bridgestone were making 13" for Super Formula recently. Perhaps these suppliers simply didn't want to pay the outrageous fees demanded by Formula One Management!?

But ultimately when 18" tyres have been racing without issue for a full season in Formula Two and they were demonstrably fine and of no issue, I don't understand how people can still be against the change.

[mzso]

Not necessarily if they have higher mass and rotational inertia. That’s another thing that’s “worse” about the 18” solution. The actual mass will be higher reducing performance in all planes, and the referred mass, from the rotational inertia, will reduce performance in acceleration and braking.

Is the mass necessarily greater? The forces are exactly the same, the wheel only needs to expand into a slightly larger volume. And even that is taken away from the sidewall which becomes less and also needs to be less strong.

By the way. Why are they still using metal wheels, instead of composites?

[Just_a_fan]

By the way. Why are they still using metal wheels, instead of composites?

Temperature? F1 brakes are silly-hot and composites aren't so good at several hundred degrees.
Impact resistance? Run a wheel against a wall and you'll likely get away with it with a nice shower of sparks to show what you've done. Do the same with a composite wheel and...?
General handling robustness? Metal wheels don't have to be handled like they're made from eggs. Composite wheels are likely to be less happy with "robust handling" in a rush, by annoyed mechanics etc.

Sometimes, just because you can make something from composite doesn't mean you should.

[mzso]

By the way. Why are they still using metal wheels, instead of composites?

Temperature? F1 brakes are silly-hot and composites aren't so good at several hundred degrees.
Impact resistance? Run a wheel against a wall and you'll likely get away with it with a nice shower of sparks to show what you've done. Do the same with a composite wheel and...?
General handling robustness? Metal wheels don't have to be handled like they're made from eggs. Composite wheels are likely to be less happy with "robust handling" in a rush, by annoyed mechanics etc.

Sometimes, just because you can make something from composite doesn't mean you should.

Well, I'm not sure about temperature resistance, but I don't think your other suggestions have much basis. Particularly the "made from eggs" comment.

[Tim.Wright]

By the way. Why are they still using metal wheels, instead of composites?

Rules mandate it on cost grounds.

Composite wheels are fine and are in series productionon a number of super/hyper cars. Composite wheels have passed road homologation for aftermarket fittment for well over 10 years now. Issues regarding impact, misuse etc were solved a long time ago. Composite wheels are not in motorsport because the technical regulations in practically every category outlaw them.

Temperature? F1 brakes are silly-hot and composites aren't so good at several hundred degrees.

Guess what the brakes are made of

[Just_a_fan]

Temperature? F1 brakes are silly-hot and composites aren't so good at several hundred degrees.

Guess what the brakes are made of

Different beasts though, aren't they? The materials usually used for the manufacture of composite wheels are not the same as those used to make carbon ceramic brakes.

I guess you could make the wheels from the same material as the brakes but would there be any benefits in doing so over a simple metal one?

[Tim.Wright]

Temperature? F1 brakes are silly-hot and composites aren't so good at several hundred degrees.

Guess what the brakes are made of

Different beasts though, aren't they? The materials usually used for the manufacture of composite wheels are not the same as those used to make carbon ceramic brakes.

I guess you could make the wheels from the same material as the brakes but would there be any benefits in doing so over a simple metal one?

There is a significant weight/inertia benefit.

[Jolle]

By the way. Why are they still using metal wheels, instead of composites?

Rules mandate it on cost grounds.

Composite wheels are fine and are in series productionon a number of super/hyper cars. Composite wheels have passed road homologation for aftermarket fittment for well over 10 years now. Issues regarding impact, misuse etc were solved a long time ago. Composite wheels are not in motorsport because the technical regulations in practically every category outlaw them.

Temperature? F1 brakes are silly-hot and composites aren't so good at several hundred degrees.

Guess what the brakes are made of

The carbon can survive, it’s the resin that melts. Carbon carbon, what brakes are made off, it too brittle to have any structural rigidity.

[mzso]

I guess you could make the wheels from the same material as the brakes

There is a significant weight/inertia benefit.

Wheels from brake disk material? They're not designed to bear mechanical loads, other than their own rotating weight.
I'm quite sure it's not viable as wheel material.

[mzso]

The carbon can survive, it’s the resin that melts.

I don't think epoxy melts...