Tires: Bias ply tires

Question
Are bias ply tires more prone to hydro planing than radial tires? Are bias ply tires still available?

Answer
Dennis,

No, if anything radial tires are more prone to hydroplaning - all other things being equal.

But the problem is that all things are rarely equal - and in the case of radial tires, there are things you can do to improve hydroplaning resistance that you can't do to radial tires (at least, not without causing a major problem is some other area, such as wear).  So in some respects, the answer to your question is the opposite of what I stated above.

Bias ply tires are still available.  In passenger car sizes, they are extremely rare and exist only in the old sizing system, like 7.00-14.  They are more available in truck sizes, and for motorcycles, earthmover, and industrial tires.