DanielPT wrote:F1000X wrote:Michelin has made very clear their '18 inch wheels or we're out' stance. Perhaps it's time for F1 to get with the times. At the same time, that might be an excuse for Michelin to put minimal development into a unique F1 tire, and instead let them just port over their LMP1 designs. It really is beyond my understanding to know if this is worthy trade off, given the potential for necessary chassis or suspension design changes to escalate costs.
What times? These times in which functionality and practicality are traded for image? There is absolutely no benefit for regular consumers by switching from 16 or even 14 to 18 inch wheels besides looks. More handling and cornering? Yeah, like they will be close to the limit except for the usual few lunatics. On top of that, they have been crashing more in the rain and we don't need those people to clog roads even more than they already are in the normal days. The only ones that benefit more from this are tyre companies that get to sell more rubber for more exotic and extortionate prices. Besides, if 18 inch wheels did wonders for open-wheels, F1 would have been racing those for a long time now. Look at FE, it's not the fault of tyres only, but it must be a contributing factor for them to be slow as hell. Michelin just want to shove that down our throats. [/EndRant]
And in the case of sportscar racing, the decision to use larger diameter, low profile tyres is tied into the way that the regulations are structured, which effectively favour that particular option.
Their regulations allow teams to use 15 inch brake discs, so that already pushes teams to run larger diameter rims in order to maximise the size of the brake discs they can use (up to the limits on the rim size, which is 18 inches). At the same time, the ACO places a restriction on the maximum wheel size which can be used - so, if a team wants to fit a large diameter rim in order to use a larger diameter brake disc, the restriction on the total wheel diameter pushes them towards a lower profile tyre overall - which therefore makes that option, overall, the optimum solution.
It's worth noting that Nissan, who originally wanted to design their car around a much smaller brake disc and to rely more heavily on their energy recovery systems to slow the cars down, originally opted for 16 inch rims and a relatively high profile tyre.
It was only when they realised that they couldn't make their hybrid system work and had to rely more heavily on the conventional brakes that they reverted to 18 inch wheels on the front, purely for the improved braking capacity (though they still stuck with 16 inch wheels at the rear, where they didn't need to boost the braking power) - indicating that it is braking, rather than cornering performance, which was the dominant factor in that instance.
As you say, for open wheeled cars where there are tighter restrictions on the brake disc size, there is less of an incentive for larger diameter rims. Even though Michelin have been selling the changes to the Formula Renault 3.5 series on performance grounds, they themselves have admitted that another major incentive was "giving the cars a more modern look", as they put it - i.e. it would be better for their marketing literature.
Why Michelin always insists on 18-inch wheels?
