Tyres - BMW M2 CS RACING 2020 Driver Manual

6.5. SETUP.
6.5.4.

TYRES.

Tyre Pressures:
The tyre pressure in a tyre has a big effect on tyre traction. The correct tyre pressure, which first should be requested at a tyre brand engineer
for the car, is in practice a narrow range of pressure, within about 3 psi. If the pressure is outside of this range, the contact patch is deformed
and not fully in contact with the road surface. The Tyre Friction Circle represents a graphical illustration of the possible total force on a wheel
in the lateral and longitudinal direction until the max. force is reached.
Setting Tyre Pressures:
▪ When the target pressure is e.g. 28 psi at hot conditions, then start with ~ 23 psi and run a stint of min. 10 laps.
After, check the tyre pressures all around and adjust to the target value.
▪ Then take the adjusted tyre set off the car and let it cool down to ambient temperature for obtaining
cold tyre pressure values.
▪ When the track gets ~10 deg warmer, bleed ~0.72 psi cold or ~1.16 psi warm air pressure
from the tyre to avoid over pressures, which results in less grip.
▪ Too HIGH tyre pressures causes sliding at slightest provocation, wheel spin and responds
to quickly.
▪ Too LOW tyre pressures makes the car feel unresponsive, rolls a lot and are slow to take a set
corners.
BMW M2 CS RACING 2020 I DRIVER MANUAL I BMW M MOTORSPORT I V02 I AUGUST 2023
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