What is the difference between radial and bias ply tyres, and what are their respective advantages? The main difference between radial and bias ply tyres is how they are constructed. Radial tyres are constructed in two parts. The casing has one layer of rubber-coated steel cables that arc from one bead to the other. Then several rubber-coated steel plies make up steel belts that are placed under the tread to stabilize the crown. These belts resist cuts and punctures.
A bias-ply tyre is made of layers of rubber-coated, crisscrossed plies of fabric placed at angles of
approximately 30 degrees. Nylon would be the fabric most commonly used. The tyre is constructed to form a single working unit, as opposed to the multiple parts that make up the radial ply tyre. Check out the below image to see a detailed visual comparison of the differences in construction between the two different types of plies.