I was at a school camp when I was about 14 or 15. A small group of us were talking to one of the camp leaders about cars (what else?) when we got on to the subject of grip.
The camp leader, a guy in his late 30’s by my estimation, stated quite convincingly that skinnier tyres were more conducive to better grip because they transferred the weight of the vehicle to the road via a smaller contact patch. A fatter tyre had to distribute that weight over a larger contact patch and so would have had a smaller amount of pressure-per-square-inch (or centimetre).
Now, I know that wider tyres are more conducive to better grip. I know it from personal experience and simply by observing the wheels and tyres fitted to vehicles that are designed primarily for high performance.
And yet the simple logic of his argument still sticks with me to this day.
Has anyone got a simple, layman’s terms explanation as to why his argument doesn’t work? Why do fatter tyres offer more grip than skinny tyres when the pressure per-unit-of-area on the contact patch would be greater for the smaller tyre?
TedY, you’re the physics guy. Your time to shine.