Back in the 70s I tested tires for BF Goodrich when radials first came out. Bias ply tires were rugged & tough & still run on tractors & heavy equipment vehicles. The issue was heat dissipation. Radials have thinner side walls and cool better, especially at high speed. Michelin coats ever strand of steel with rubber & they wrap their molds around the tire rather than smash it in a horizontal mold. So I run Michelin on every vehicle if I can. They run cooler & have better construction. But I still wouldn't go with Bias ply because their chance of falure is a lot higher at high speed. Not sure what I'll replace my Michelin CT Primacy with when it wears out.