Tyre challenges for 2006

With the return of tyre changes next year, the manufacturers will have plenty of work to do before the start of the season...

In Formula 1, the tyres have a major role to play. They need to resist 1.6 tonnes of vertical load at 300 kph, 2.2 tonnes of lateral load in a 150 kph corner, and 2.5 tonnes under braking. All of that while offfering optimum, consistent performance. In 2005, the cars had to use the same set of tyres from qualifying to the end of the race; but for next year, the regulations will once again allow tyre changes. It's a fundamental modification to the rules, and the engineers are already hard at work adapting to it...

The Renault F1 Team's partner Michelin will face a complex challenge in order to develop the most competitive tyres possible for next season. They will have to strike the balance between consistent performance from the first to last lap of a stint, and compounds soft enough to set competitive times.

Each circuit has its own characteristics (asphalt properties, ambient temperature, circuit layout), so the aim is not to develop a single tyre, but a range of appropriate solutions. Each car also uses its tyres in a different way, so they evolve to suit vehicle's demands as development progresses. Here are the key parameters the teams and manufactures will be looking at:

1. Finding the right compound. As improbable as it may seem, a tyre needs to spin a small amount (less than 1%) to move forward. If a tyre is too soft, it will suffer severe degradation after a few very fast laps. Too hard, and it will perform consistently but slowly. Finding the right balance is far from straightforward.

It comes from a blend of 220 ingredients, indlucing oil, carbon and synthetic rubber. For 2006, the goals will be almost the opposite of 2005: wear will be less of a preoccupation, because the tyre life will go from 350 km to just 100 km. In general, we can expect to see softer tyres used next year.

2. The best construction. The tyre's construction is intimately linked to the compound of the rubber. The construction is the term for the tyre's 'skeleton', a mixture of synthetic fibres (nylon, polyester, carbon) on which the compound 'sits'. The stiffness of the sidewalls, and the flexibility of the contact patch, are crucial. While tyre constructions in 2005 were conceived to help the tyre last a full race distance, they will now be optimised to deliver maximum performance over a single race stint.

3. Looking after the tyres. The car's set-up plays a fundamental role in tyre behaviour, and therefore in their performance. In order to obtain a good car balance, temperatures theoretically need to be identical across the contact patch, at an optimum level of around 90-100°C, of all four tyres, front and rear, left and right. The Renault F1 Team uses specialist tools to reach the optimum levels. In 2005, the team would set the car up to look after the tyres -- a fact that could sometimes cost a little performance.

From this winter, they will once again be able to concentrate on pure performance. The primary area to be affected will be the mechanical set-up of the car: camber and toe-in, as well as spring and damper settings, allow the team to reach optimum tyre temperatures. Furthermore, differential settings, brake balance, tyre pressures, weight distribution and traction control settings all have a role to play.

The first indications of the balance of power will come when testing recommences, at the end of the month. The priority will be to begin learning about the challenges a 100 km tyre faces under next year's V8-powered regulations. There is only one way to do that -- plenty of laps!

-renault-