In the size of tire the designation would have a R. Example 130-90 R 16. What’s the difference between radial tires and bias-ply tires?
The main difference between radials and bias-ply tires lies in their construction. Tires aren’t just toroidal balloons, they are reinforced with cords of steel or synthetic materials such as nylon or Aramid. In bias-ply tires, the fibers are wrapped in an X pattern between the beads; in radial tires, the fibers are wrapped perpendicular to the tread. Radial tires have more flexible sidewalls than bias-ply tires, and thus absorb road irregularities better and have a comparatively larger contact patch when leaned over. Because of the flexible nature of a radial, these offer higher mileage compared with a comparable bias-ply for a given rubber compound. Since they absorb small road irregularities better, they ride more comfortably and are less likely to be upset by groovy pavement.
While radial tires perform better than bias tires, some older motorcycles can’t be fitted with radial tires because of differences in rim profiles. You probably won’t notice much of a difference anyway, so stick with boas tires if that’s what the motorcycle was designed for.
Why can’t I mix radials and bias tires?
The different ways in which radial and bias tires react to sideways loads can lead to unpredictable behavior while cornering. It’s bad enough to do this on a four-wheeler, but it can be even worse on a motorcycle. If you need to replace one tire and the same type is not available, then go ahead and replace both tires with the same type.
