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I noticed I am in more need of replacing my tires on my 39 Six than expected. It currently has tube type (make I can't even find to compare - Bedford Air Coaster, 3 inch white walls) but the greater question I have is bias ply vs. radial? I really don't know enough to gauge what makes the most sense or what are real considerations and I have seen Coker only does the bias ply.

Separately, the whole white wall vs. not is secondary but also one I'm feeling out. I have seen some non-white walls in old photos that looked nice but I think part of what made those appealing was the side "etching" (like these though they are white walls).

Opinions, experiences, etc. appreciated. Also, any tire sites along the same.

Thanks.

Surprised you could even get radials on a 39. It's my understanding that the more "bicycle-shaped" the tire is, the less it matters. Correct me if I dreamt this up or something.

Though it's worth noting that all bicycle tires are bias-ply as radial tires give a weird feel, like having a flat tire.

To be fair, I haven't come across radial in my searches so your point on only bias ply is likely 100% right. I thought I had seen radial being referenced or maybe I was thinking about tube vs. tube-less. Regardless, any corrections regarding my search, etc. are appreciated as I negotiate this. At this point, my one tire is such that I am not driving (spare is bad/worse).

I did find these radials after all:

https://dbtires.com/product/auburn-deluxe-radial-15-16-sizes/

Installed new bias ply 700-16 Firestones on my 120. Ride beautifully, do not 'track' like I was worried about. Whole heartedly endorse them.
Be sure and run the PSI as per the owner's manual to get the most out of your ride.
Bob J.

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The manual recommends 22 PSI for my '37 120 convertible coupe. That seems ridiculously low to me. I have new 7.00 / 16 Firestone WWW tires on it, and it rides very smooth at 22 to 26 PSI cold, but it handles better on pavement with 28 PSI cold. These tires are 4 ply polyester, and should ride very smooth. The car tracks straight with 3.5 degrees caster. The tire pressure goes up several PSI after a few miles, even in cool weather and starting at 26 psi or so. Using nitrogen instead of air might keep the pressure more stable. This car seems to have a shudder or wheel tramp on some rough paved roads. The tires show to be balanced and the wheels appear to be straight and in good condition. The brakes work very well, and the steering is tight. The car does not have a front stabilizer. I wonder of adding one would improve the ride on bumpy paved roads. (?) Pavement around here on the 2 lane roads is in poor condition, and years of adding a seal coat of tar and gravel has left them bumpy and with some minor washboarding.

I have put Auburn 700/16 radials on my 37. The change in handling is so much better driving at highway speeds. I was also pleasantly surprised that the stock wheels allowed me to run them tubeless. The price for four in Canada was quite shocking but having driven on them half the summer I should have done it when I first finished the restoration

The tire pressure in the manual applies to the original type and size of tires.

Anything newer/different may require a different pressure.

Yes, probably but it would take major engineering to determine what it should be. Best to start with the manufacturer’s suggestion and adjust from there bases on wear but in no event use the pressure printed on the tire itself as that’s typically a maximum rating.

The Firestone tires I am using are supposed to be identical to the original except for having polyester cord, which ought not matter.