Improving tires: the weak link in world's fastest cars.

[g-force_addict]

IMO they shouldn't use conventional belted tires at all no matter if they are radial or bias ply.
Just Googleing belted tires you get plenty of attorneys offering litigation for tread separation. And this on road tires at low speeds.
So unless the belts aren't strongly secured to the tire bead by overlapping cords or something they are a no go.

High speed tires usually use cap plies that are supposed to prevent belt separation.
http://s.hswstatic.com/gif/tire-cutaway-big.jpg
AFAIK cap plies don't run all the way to the tire bead
http://dasselaw.com/images/NOC_F6.jpg
So only the adhesive power prevents the belts from separating at speed.

Steel binds poorly to rubber so steel belts are reportedly more prone to separating at high speeds than those made of Nylon, Kevlar or some other textile materials.

This seems to confirm that radial belted tires are indeed weaker by themselves as the belts are not directly attached to the bead.
Carroll Smith wrote in Tune to Win (1978):
http://books.google.com.gt/books/about/ ... edir_esc=y

'If the cords are arranged radially the tire will have the softest ride possible with maximum self dampening but will have no lateral stability.
This is why radial tires require circumferential belts, preferably of steel.
Racing tires at the time of writing, cannot accept the weight or the rigidity of the belts.
On the other hand, if the cords were arranged circumferentially the tire would have excellent lateral stability, a very harsh ride and it would be impossible to hold the profile shape.
So, borrowing a page from the tailors' and sailmakers' books. the cords of the racing tire are arranged on the bias, thus providing strength in three planes simultaneously.
Racing tire cord angles are closer to the circumferential than passenger bias tires in order to provide smaller slip angles for a given cornering force and a more efficient tire -as well as to provide more support for the wide profile.'

So this explains why true radials are seldom used in (hardcore) racing.
Even Formula 1 tires are actually bias-ply. Although the cord angle is smaller than those tires actually called bias ply.

[g-force_addict]

Yet another argument against steel belts as they can separate at high speeds

'A long-standing problem encountered in the employment of solid tires on industrial vehicles operated in heavy or arduous service over broken or uneven surfaces such as are encountered in mills, mines and similar locations has been that such tires so employed have been subject to early failure due to cutting, chipping or chunking. Attempts have been made to solve this problem by the employment of a wire loaded rubber in the body or tread layer of the tire. Such attempts have proceeded on the theory that wire loading would reduce reflection and thereby permit the tire to ride over obstructions.

While such an approach has been successful in reducing early tire failure by cutting, chipping or chunking, it has resulted in the introduction of new sources of early tire failure. The most important of these has been the tendency of the Wire loaded layer to separate from the rest of the tire. Attempts to solve this tread separation problem by increasing the thickness of the wire loaded layer have merely shifted the plane of tread separation radially inward in the tire.'
http://g.icodex.org/patents/US3179148

Now I will contact some salt flat runners to see if they have some details on the construction of land speed record tires.

[Tim.Wright]

AS far I know, the LSR cars use solid metallic wheels.

[Lycoming]

AS far I know, the LSR cars use solid metallic wheels.

The older ones don't always, but the newer ones (Thrust SSC, Bloodhound) use solid aluminum wheels.

[Ciro Pabón]

Lycoming, you´re right, not always, but the last record holder of a car moved by internal combustion engines, as opposed to turbine/jet or rocket cars, used aluminum wheels.

1947Railton Mobil Special, 634.39 km/h, two 24 liter Napier Lion engines, solid aluminum wheels. A beast, the fastest car in the world, if you ask me. After it we have had low flying airplanes...


Dear g-force addict (that`s a nick I like!), I believe you might be interested in a thread we already had about what I thought was a pretty interesting possible solution.

Feel the awe of Spherical Wheels: magnetic (or even air) bearings, thus computer-controlled electric suspension with potential for less effective unsuspended mass, as the tyres are not attached mechanically to the car, better tyre shape for centrifugal resistance (a shell works better than a disk in tension and in compression), less width in flexion for rolling resistance, BUT the ability to steer by twisting less the contact patch (contact ring?) because the tyres are not fixed to an axle and because you can steer all of them by computer. An entirely different dynamic for cars


Mortals, I give you The Ballbot. After watching this video, imagine the dynamics of a car with FOUR steerable wheels


So, how about sidestepping those contact wheels on the top of the sphere? Could it be possible to get rid of them? How?

After all, if you don´t, you would only move the problems of current wheels to those tiny wheels seen on the previous video on top of the sphere, right?

So, how we build the ¨Audi's I-robot¨ car of the previous image?

Well, what if someone were able to create a Kinematic Design and Commutation of a Spherical Stepper Motor?

Behold, puny humans! The tyre of the future... if Pirelli is finally enlightened


Pirelli enlightened! Hahahaha, good one.

I imagine I don´t have to spell the advantages of a spherical marvel over an ordinary and boring cylindrical wheel, even to beings of this planet, but I think it deals with most of the problems you state, g-force (and, of course, creates some of its own reap).

So, do not improve the tyre.

Simple. Do what engineers do all the time: reinvent the wheel.

San José State University bike. 15 mph but cool