Simplify the following text for a Grade 6 native English-speaking person.
Original: High performance tires have small void ratios to provide more rubber in contact with the road for higher traction , but may be compounded with softer rubber that provides better traction , but wears quickly .
Simplified: Tires are made of different types of rubber . Softer rubber is used in summer or when the tires need better traction , for example , in auto racing .