Tyre widths

[Simon]

you are wrong, wider = better traction.

do you seriously think everybody including car manufacturers, tuning houses and race teams have been getting it wrong for all this time?

LOL. in water thinner tyres are better. Rally cars use thin tyres in the snow for similar reasons

 

[Clarkey]

obviously, and I was talking about dry tarmac.

 

[Simon]

obviously, and I was talking about dry tarmac.

The original post was about the wet

 

[Clarkey]

thats not the way I read it. It mentions poor aquaplaning in the wet on a wide tyre which is fair enough, but then says 'so arguably a narrower tyre will always rule'.

 

[theo]

Would body roll during acceleration and deacceleration not affect this in the same way as cornering? After all it's the same kind of centre of mavity shifting princable. So saying the wider tyres are better for cornering would mean thay are better for accelerating and deaccelerating.

Best example i can think of would be the flex of the tyre's rubber and the point of limiting friction. If the thinner tyre has better support from the sidewall then it will have less flex as per say which mean it will not deform as much which will reduce the maximum size of the contact patch as forces is applied through the wheel. Whilst the wider tyre will deform more which would mean more contact at point of acceleration which mean inceased grip so can put more force through the wheel without slip.

Feel free to debunk anything i'm saying here, i'm only going at it from a physics understanding here, not a learned petrol head.

 

[Simon]

The main benefit of wider tyres is less deformation in terms of slip angles due to the shape of the contact patch

 

[theo]

The main benefit of wider tyres is less deformation in terms of slip angles due to the shape of the contact patch

But would there not be more possible deformation down the the centre of the tyre in strait line acceleration/retardation?

 

[Simon]

But would there not be more possible deformation down the the centre of the tyre in strait line acceleration/retardation?

Not sure, I'm not much of a tyre expert. Side wall profile and stiffness will have a large effect though

 

[Jonnycoupe]

you are wrong, wider = better traction.

do you seriously think everybody including car manufacturers, tuning houses and race teams have been getting it wrong for all this time?

Lateral or tractive traction?

The dont get it wrong, they tune to a specific application, however this can be wrong for a wet B road with puddles.

 

[Jonnycoupe]

Do you really think that after all that research, they'd never have discovered that the best traction doesnt come from the widest tyres possible ?

Maybe it actually does but the aerodynamic compromises is too much of a hit and actually makes the car slower on the straights, but then minimising the width whilst makes you super fast on the straights but totally kills your corner speed.... ah yes CAR tuning and setups.

Try looking at the overall picture

 

[Jonnycoupe]

so why dont car use bike tyres?

Slip angles work differently to camber thrust

I think the point you are trying to make is the area on the ground vs the pressure on the ground. Bigger tyres = more surface area, but less pressure on that surface area so same grip? i doubt it works that way really?

There isnt more area if you run the same tyre pressures, the footprint is wider but not as long on wider tyres. Think of a rectangular tyre footprint on the road rather than square

 

[Jonnycoupe]

Are you telling me the contact patch of a Fiat Panda is the same as that of a Porsche 911 Turbo?

why would they be? The porsche is significantly heavier and requires more of a reaction from the road.

 

[Jonnycoupe]

Amazing, I'd better phone up Bugatti right away and inform them that the 365 section rear tyres on the Veyron are too wide, would be better on some 225's.

If they were about to start a race in soaking wet conditions they may reply with 'We already have'