F1 tyre profiles
Author
Discussion

Varn

Original Poster:

205 posts

230 months

Saturday 25th April 2009
quotequote all
Always wondered why F1 tyres have such high profiles. What are the reasons for this? If there is a rule regarding this issue, what is its purpose?

Asterix

24,438 posts

257 months

Saturday 25th April 2009
quotequote all
Advertising for the manufacturers... wink

Never known, something to do with handling and set up? If they had very low profiles then maybe less adjustability?

Northern Munkee

5,354 posts

229 months

Saturday 25th April 2009
quotequote all
they mentioned in the commentary, 13inch wheels are the rules and have been for a long time.

although given there is barely any suspension anyway, like a kart, which has none, flex in the tyre wall is essentially the only suspension. so the bigger (the tyre wall) the better. It might be the case if it ain't broke why fix it, some teams have 20-30 years data and experience with 13inch wheels, in relation to suspension and chassis design & development.

Edited by Northern Munkee on Saturday 25th April 16:22

elster

17,517 posts

239 months

Saturday 25th April 2009
quotequote all
Why would you change it to low profile tyres?

SamHH

5,078 posts

245 months

Saturday 25th April 2009
quotequote all
As mentioned, the rules specify a maximum wheel diameter of 13", and I guess there is no reason for the rules to be changed to say anything different.

rdjohn

7,169 posts

224 months

Saturday 25th April 2009
quotequote all
Gazboy said:
elster said:
Why would you change it to low profile tyres?
Less lateral movement? It's interesting that in series that do not specify a wheel size or tyre profile or if there is a limit then the teams usually go for a huge wheel and a very low profile tyre. BTCC wheels were huge with very small tyre profiles before the big shake upor rules & regs.
I think that the tyres are low-profile, it is just that the widths are huge compared to what can be fitted into a BTCC car.

IMHO the tyre sizes are not the problem at the moment - going back to having adjacent compounds for the race is what is needed, as demanded by Alsonso last week. Selecting the optimal tyre and then going hard and soft either side of it is simply stupid.

Northern Munkee

5,354 posts

229 months

Saturday 25th April 2009
quotequote all
Spookily a troll on google brought this up on the subject, starting from a different perspective, but the arguments are sound...

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

skinny

5,269 posts

264 months

Saturday 25th April 2009
quotequote all
Gazboy said:
elster said:
Why would you change it to low profile tyres?
Less lateral movement? It's interesting that in series that do not specify a wheel size or tyre profile or if there is a limit then the teams usually go for a huge wheel and a very low profile tyre. BTCC wheels were huge with very small tyre profiles before the big shake upor rules & regs.
it's not like you get massive lateral movement in the tyre sidewall even with 5g cornering tho...

they only *need* bigger wheels if they need bigger brakes, which they dont.

SamHH

5,078 posts

245 months

Saturday 25th April 2009
quotequote all
rdjohn said:
I think that the tyres are low-profile, it is just that the widths are huge compared to what can be fitted into a BTCC car.
Approx 45 profile.

stephen300o

15,464 posts

257 months

Saturday 25th April 2009
quotequote all
The old Gumball fat profile tyres look sooo much better than the low profile ones. And that's obviously the main thing. smile

Alfie Noakes

1,307 posts

299 months

Saturday 25th April 2009
quotequote all
As far as I know the wheels are 13" dia becuse Max likes the look of them.

The main advantage if they went for bigger wheels is bigger brakes which would mean more stopping power for less money.

I'm not sure how the relative stiffness of a lower profile tyre would affect the design of the car but I assume it would allow them to make the suspension more compliant.

The only disadvantage I can think of to lower profile tyres is that there would be less scope for handling adjustments via changes in tyre pressure.

Just a guess though.

Varn

Original Poster:

205 posts

230 months

Wednesday 29th April 2009
quotequote all
Ok thanks guys smile

More questions I'm afraid:

- Why are the tyres alot thinner than they used to be?

- Why are the backs and the fronts the same diameter (tyre heights) these days?

I'm guessing the answer for both is going to be rules!

Are they at a disadvantage not being able to choose different diameters for front and back, if so why?

Northern Munkee

5,354 posts

229 months

Wednesday 29th April 2009
quotequote all
here's a place to start.

http://en.wikipedia.org/wiki/Formula_One_tyres

The main answer is rules, no tyre manufacturer is going to supply different diameter tyres for each team, can you imagine the extra production costs involved in that, and cries of favouritism, especially in what is a one make tyre formula, would rather defeat the cost saving, safety (performance control).

That said special tyres have been produced in the past, the obvious one was the front tyres for the 6 wheeled Tyrrell, the designer (gardner? Poslthewaite?) reasoned a smaller front profile aerodynamically, so less drag, with a greater contact patch from 4 tyres at the front for grip. This was eventually done away with by a rule change I think (each car must 4 wheels and no more).

The FIA are bringing in rules to make the front wheels narrower from next year, again doubtless a performance control to reduce laptimes/cornering speeds, now that we're back on slicks, as opposed to grooves, in the same way they narrowed the front track, and then the tyre war between Michellin and Bridgestone saw the front tyres get wider. Rear wheel tyres used to be much wider early 70's-80's because the rules allowed and the strength/sophistication of tyre construction has improved performance. Its also worth pointing out that the change from cross ply to radial construction has had a significant effect on the performance and a reduction in the sideways action between the 60's and 80's.

If they all have the same tyres then no one is at an advantage or disadvantage.

Also one can't separate aerodynamics from tyres. In so much as F1 cars from ground effect onwards have gained its grip from a carefule balance between aero and tyres, and so much more is known about aero, plus the aero elements are much much bigger and efficient that the 70's, simplistically put, squashing, tyres into the track, so the contact patch is bigger, generating more grip, than the fat tyres of the 70's but also necessitating stronger sidewall construction.

Nothing advances on a F1 car in isolation of other parts of the car.



Edited by Northern Munkee on Wednesday 29th April 12:04

rev-erend

21,619 posts

313 months

Wednesday 29th April 2009
quotequote all
My guess is Weight.

Rubber is always lighter than alloy ..

jon-

16,534 posts

245 months

Wednesday 29th April 2009
quotequote all
Rules, and aesthetics. We expect F1 cars to ride on big rubber, they would look stupid on big alloys and low profile wheels.

The tyre is the first point of the suspension and is VERY hard to predict how it will react and there for control. If the designers had their way, they would use as low profile as possible and build a more controlled flex into the wishbones.

skinny

5,269 posts

264 months

Wednesday 29th April 2009
quotequote all
rev-erend said:
My guess is Weight.

Rubber is always lighter than alloy ..
in F1 the wheel weighs a small fraction of the tyre - i'd say from picking them up and estimating, at least 10 times less.

Edited by skinny on Wednesday 29th April 13:00

jon-

16,534 posts

245 months

Wednesday 29th April 2009
quotequote all
skinny said:
rev-erend said:
My guess is Weight.

Rubber is always lighter than alloy ..
in F1 the wheel weighs a small fraction of the tyre - i'd say from picking them up and estimating, at least 10 times less.

Edited by skinny on Wednesday 29th April 13:00
And in a lot of cases now, car wheels too.

My 16" wheels are 5kgs, the 16" tyres around them are about 8kgs.

anonymous-user

83 months

Wednesday 29th April 2009
quotequote all
Northern Munkee said:
they mentioned in the commentary, 13inch wheels are the rules and have been for a long time.

although given there is barely any suspension anyway, like a kart, which has none, flex in the tyre wall is essentially the only suspension. so the bigger (the tyre wall) the better. It might be the case if it ain't broke why fix it, some teams have 20-30 years data and experience with 13inch wheels, in relation to suspension and chassis design & development.

Edited by Northern Munkee on Saturday 25th April 16:22
Modern F1 cars have a lot of suspension movement and a lot of tyre flex, thats how they ride the kerbs so well. Watch one from the back into a corner like Beckets, they roll a lot. Tyres are relatively undamped compared to the other movement in the suspension, so it's not a good thing to have large sidewalls on a smooth surface like a racetrack. The reason they are the way they are is down to the regulations, if it was a free for all they would be very different.