Bias Ply or Radial? A Look at Which Tire to Choose for a Classic Car Build
If you head on over to our online classic car gallery, you'll see a great many classic cars and vintage vehicle restorations, many of which boast bias ply tires. However, that doesn't mean they are the only pick or the best pick in all cases. The specialty tire market is largely divided into the two big segments: bias ply and radial. The following is a quick look at both and what they have to offer to vintage car owners who want to give their vehicle a classic car gallery kind of look and feel:
The Basics of Basic Ply Tires
The name 'basic ply' refers to the tire's internal construction. This segment of tires have cords or 'plies' that run at a 45-degree angle from bead to bead. This creates a diagonal pattern that gets crisscrossed with every added layer to create a very rigid structure.
When it comes to the classic car market, these bias ply tires are generally found to be more desirable or more authentic given that they are older and were generally the type of tire originally found on all American automobiles sold before the 1970s. You can tell a bias ply tire by its narrow tread profile and sharp shoulder that gives it a pie crust-like look with a sidewall bulge.
The problem with bias ply tires (and why the construction and style were replaced) is that they are finicky and don't have great handling characteristics. The design's rigidity means they don't as readily conform to road surfaces as more modern tires and so they will follow deep road breaks and ruts. This creates the sensation of the tires 'wandering' or slightly slipping from their intended course.
The Basics of Radial Tires
If you are more interested in driving your classic car than having it as a living classic car gallery piece, then radial tires are likely a better pick. Radial tires have a more modern construction that consists of ply cords that run 90-degrees to the bead. This creates a radial orientation that makes the tire more flexible so as to better conform with the road surface. Radial tires will neatly skim over pavement ruts and breaks and offer significantly better handling over rough roads and poor weather conditions.
The issue with radial tires, at least for classic car enthusiasts, is that they aren't authentic and they boast a more modern appearance. Most brands of radial tires will feature a wider tread surface with rounder shouldering in comparison to bias ply tires. Radial tires also feature what's called a tread siping, a design facet that better sheds water from the treading for better traction on wet and icy surfaces.
Learn More & See Examples at CHRA
Now, there is an exciting number of tire companies that are bridging the gap between the classic look of bias ply tires and improved handling characteristics of radial tires. Contact us to learn more about these and other options for tires on your classic car restoration.