2022 Tyres Thread

[JordanMugen]

IMHO it’s the rippling sidewalls that allow them to ride the kerbs. The tyres conform to the kerbs keeping maximum contact patch.

Yet a V8 Supercar rides kerbs just fine with a 18" tyre with much less sidewall than that proposed for F1. I think having a large amount of suspension travel available and the use of a spool (non-)differential has a lot more to do with good kerb jumping ability...

If taking the kerb is quicker, they'll take it - cool or otherwise.

Having a short sidewall tyre does not preclude a car from using a kerb! It is, rather, a matter of the available suspension travel... Indycar rides the kerbs just fine as it uses reasonable sized coil springs and shocks... The F1 designers have become addicted to their 13" tyres and fit their vehicles with "mini" sized springs and shock absorbers... They may need to reconsider that.




Dallara DW12

vs

Toro Rosso STR13

Will low profile tyres require the suspension to be stronger?

Not stronger, but it will need to have more travel. As you can see above the F1 suspension components are undersized compared to the normal components used in other open wheel series.

Compare the rear suspension for instance...

The robust rear damper unit used in the Indycar:


The F1 rear damper is so tiny, it is not even visible in the drawing, hidden somewhere down by the exhaust manifold.

[FW17]

IMHO it’s the rippling sidewalls that allow them to ride the kerbs. The tyres conform to the kerbs keeping maximum contact patch.

Yet a V8 Supercar rides kerbs just fine with a 18" tyre with much less sidewall than that proposed for F1. I think having a large amount of suspension travel available and the use of a spool (non-)differential has a lot more to do with good kerb jumping ability...

https://nnimgt-a.akamaihd.net/transform ... 8_fmax.jpg

If taking the kerb is quicker, they'll take it - cool or otherwise.

Having a short sidewall tyre does not preclude a car from using a kerb! It is, rather, a matter of the available suspension travel... Indycar rides the kerbs just fine as it uses reasonable sized coil springs and shocks... The F1 designers have become addicted to their 13" tyres and fit their vehicles with "mini" sized springs and shock absorbers... They may need to reconsider that.

https://cdn-1.motorsport.com/static/img ... -matta.jpg

https://www.racecar-engineering.com/wp- ... pir12a.jpg
Dallara DW12

vs
https://pbs.twimg.com/media/D2WN1oHWkAATgSs.jpg:large
Toro Rosso STR13

Will low profile tyres require the suspension to be stronger?

Not stronger, but it will need to have more travel. As you can see above the F1 suspension components are undersized compared to the normal components used in other open wheel series.

Compare the rear suspension for instance...

The robust rear damper unit used in the Indycar:
https://s3-eu-west-1.amazonaws.com/cras ... 148982.jpg

The F1 rear damper is so tiny, it is not even visible in the drawing, hidden somewhere down by the exhaust manifold.
http://www.thepaddockmagazine.com/wp-co ... 50x670.jpg

That is not the case, that other open wheel series have larger springs

F1 had larger springs at the beginning of the era after active suspension. But with years of development they have managed to reduce the size of the components while doing the same (and a lot more) functions

[henry]

I’ll quote James Key:

Will there be a bit of grip loss for those different 18-inch rim tyres? Maybe, they’ll be different animals.

https://www.racefans.net/2019/09/25/rac ... p-25-09-2/

So he’s not expecting large gains from being able to design suspension with more travel. Quite possibly the reverse. He may be referring to the narrower fronts but in that case I think he would have said so directly.

[izzy]

I’ll quote James Key:

Will there be a bit of grip loss for those different 18-inch rim tyres? Maybe, they’ll be different animals.

https://www.racefans.net/2019/09/25/rac ... p-25-09-2/

So he’s not expecting large gains from being able to design suspension with more travel. Quite possibly the reverse. He may be referring to the narrower fronts but in that case I think he would have said so directly.

i noticed this. I don't get the physics of why there won't be more grip, for a given tread width as you say, with basically more control over the contact patch with having a shorter sidewall. They should be able to load the tread more evenly, especially at the edges and especially the inside edge.

[FW17]

I’ll quote James Key:

Will there be a bit of grip loss for those different 18-inch rim tyres? Maybe, they’ll be different animals.

https://www.racefans.net/2019/09/25/rac ... p-25-09-2/

So he’s not expecting large gains from being able to design suspension with more travel. Quite possibly the reverse. He may be referring to the narrower fronts but in that case I think he would have said so directly.

i noticed this. I don't get the physics of why there won't be more grip, for a given tread width as you say, with basically more control over the contact patch with having a shorter sidewall. They should be able to load the tread more evenly, especially at the edges and especially the inside edge.

Maybe because the driver can call for max torque and the tread does not give up and slip, but rather the side walls flex

[Just_a_fan]

The stretched tyre is only a fashion amongst a small minority.

A small minority of car manufacturers and their original fitment tyres?

https://anythingauto.co.uk/wp-content/u ... 60x640.jpg

https://images.autotrader.com/scaler/62 ... 250627.jpg

They aren't "stretched tyres", they're low profile with a large wheel protector rim incorporated above and outside of the bead. The tyre protects the expensive alloy wherl this way. Quite common on all types of tyre.

[strad]

world of difference between "wrinkle wall" slicks and any other racing tire.

[izzy]

Maybe because the driver can call for max torque and the tread does not give up and slip, but rather the side walls flex

oh cool. what happens when the sidewall can't flex any more? or are they those everflexing kind?

[henry]

I’ll quote James Key:

Will there be a bit of grip loss for those different 18-inch rim tyres? Maybe, they’ll be different animals.

https://www.racefans.net/2019/09/25/rac ... p-25-09-2/

So he’s not expecting large gains from being able to design suspension with more travel. Quite possibly the reverse. He may be referring to the narrower fronts but in that case I think he would have said so directly.

i noticed this. I don't get the physics of why there won't be more grip, for a given tread width as you say, with basically more control over the contact patch with having a shorter sidewall. They should be able to load the tread more evenly, especially at the edges and especially the inside edge.

My understanding is that current F1 suspension does not follow a simple spring and damper model. It is much more sophisticated and in particular includes another control element, the inerter. This means that even though the tyre has a low spring rate and light damping it is maintained in contact with the road, and being in contact it’s localised flexibility allows it to conform to the road surface, no matter how rough, with a large contact patch. The 18” solution may be able to maintain similar contact patches but it’s localised stiffness will prevent it conforming as much and so will have a smaller contact patch.

As for the physics, here’s a basic description of inerter function, https://www.highpowermedia.com/F1-Monit ... he-inerter
And here is Prof Smith’s original paper about it. https://pdfs.semanticscholar.org/f791/a ... 1569434358

[izzy]

My understanding is that current F1 suspension does not follow a simple spring and damper model. It is much more sophisticated and in particular includes another control element, the inerter. This means that even though the tyre has a low spring rate and light damping it is maintained in contact with the road, and being in contact it’s localised flexibility allows it to conform to the road surface, no matter how rough, with a large contact patch. The 18” solution may be able to maintain similar contact patches but it’s localised stiffness will prevent it conforming as much and so will have a smaller contact patch.

As for the physics, here’s a basic description of inerter function, https://www.highpowermedia.com/F1-Monit ... he-inerter
And here is Prof Smith’s original paper about it. https://pdfs.semanticscholar.org/f791/a ... 1569434358

awesome thanks

[strad]

Lot of reading there but from this part :

One area where inerters are of particular use is on vehicles with large tyre sidewalls, such as those in Formula One. A large sidewall is more prone to uncontrolled deflection at high suspension frequencies, which an inerter can be highly effective at combating, the result being a more consistent tyre contact patch and thus greater mechanical grip.

I deduce that an inerter will be of far less importance if used at all.

[henry]

Lot of reading there but from this part :

One area where inerters are of particular use is on vehicles with large tyre sidewalls, such as those in Formula One. A large sidewall is more prone to uncontrolled deflection at high suspension frequencies, which an inerter can be highly effective at combating, the result being a more consistent tyre contact patch and thus greater mechanical grip.

I deduce that an inerter will be of far less importance if used at all.

That may be the case, although I think they have been used on LMP1.

[FW17]

Mclaren testing 2021 rim style?

[cplchanb]

Mclaren testing 2021 rim style?

https://d.radikal.ru/d27/1909/9a/7e787722bc67.jpg

Prob just transport or scrap rims for practice

[strad]

that's not an 18 inch rim.