Contact patch - the risks due to under and over inflation
The tyres of your car may seem imposing to you, as if solidly anchored into the ground, but in reality the contact with the road is very often no more than a few squared inches of rubber. You want to preserve these few inches like the apple of your eyes, so stick to these few basic rules
The contact patch of a tyre is always limited in size, even in optimal conditions. It means you have to monitor your air pressure regularly because any significant discrepancy may cause several inches of contact to be lost as illustrated below :
Pressure must be checked regularly as appearances can sometimes be misleading.
Another point to watch the camber angle. As we explained in our guide, the bigger the camber angle, the less in contact with the road the tyre is:
A strong camber angle allows to take sharp turns but it comes at the expense of loss of contact patch
Put together, these elements can definitely make a difference between a smooth ride an an accident .
The contact patch must be regularly monitored in order to prevent the risks of aquaplaning. Please note that aquaplaning risks depend as much on the area of the contact patch as on the tread depth
Relation between aspect ratio and contact patch
As illustrated below, the shape of the contact patch may vary according to the aspect ratio of a tyre, whether big ( 65) or small ( 35).