Radials and Bias Plies

[highcking]

I am about to put new tires on my '58 Roadmaster. Choices are 8.00x15R and 8.00x15. On my '58 Century which I drove to car shows for some 15 years, I used radials and was very happy with the way the car handled. I also own and drive a 1960 Chevrolet with radials (no PS) and a '56 Fairlane (with PS) with bias plies. Today I did some highway driving with the Chevy and Ford and was reminded of the superiority of the radials in terms of handling and road-steadiness. Chevy has no squeal on corners and the 20-year-old tires still look brand new. 

 

It would be an easy choice if the American Classic 8.00x15R tire had a 2-1/2" whitewall instead of 3-1/4" which is really too wide for a '58 Buick. However, this will not be a judged car and I am pretty uneasy about driving this 5,000 pound monster at 75mph (hopefully for next summer's BCA national shows) on bias plies. So I am leaning towards the radials. Any strong arguments to the contrary?

 

Bill in Luray Va.

[JFranklin]

Maybe go black-wall or modern white-walls.

[JohnD1956]

A few thoughts:

20 year old radials may look new but thats a long time. I n my experience you will find dryrot on newer radials before ten years.

 

Most retailers can get customized white wall widths for not a lot more per tire. The problem may be that they are then considered special orders and not returnable if you don't care for that look.  

 

I bought 2 1/2 inch white walls on Toyo tires for my '56 from Diamondback tires.  Keep in mind that the bead of the rim will cover over part of the whitewall.  I am very satisfied so far for 3 years and roughly 5000 miles.  They will cause loss of points should it ever be judged.  Thats not a concern for me. 

 

Good luck.

[jensenracing77]

If points don't matter I would pick radials every time. I even chose radials on my high end restoration that was getting judged and took the points deduction. I was not going to pay another $1500 for another set of tires and restoring wheels just to save 8 points. 

[highcking]

Jensen racing - I agree. Bias plies would I think deter me from driving the car at all. I sure wish some vendor made the big radials with a 2 or 2-1/2 inch stripe, though. The 3” plus style went out on most makes around 1957.

Johnd - thanks for reminding me about Diamondback! I’d forgotten about them entirely.

 

[Barney Eaton]

Go with the radials on a non-judged driver.     

There is a small concern with putting radial tires on rims designed for Bias tires.....  the thought is the radials transfer more forces to the rim of the wheel and

might cause a rim failure.     While in theory this could be a problem but I have never know someone that has had a rim failure because of radial tires. 

The is hardly an issue on cars like most of ours that are not driven hard into corners and abused.    

 

[Bloo]

1 hour ago, highcking said:

I sure wish some vendor made the big radials with a 2 or 2-1/2 inch stripe,

 

Check with Diamondback about that. I think they can do almost anything, even triple stripe. I have a special-ordered 600-R-16 sitting in my garage with a 2-1/4" whitewall (2-3/4 is the narrowest in the catalog).

 

4 hours ago, JohnD1956 said:

 

I bought 2 1/2 inch white walls on Toyo tires for my '56 from Diamondback tires.  Keep in mind that the bead of the rim will cover over part of the whitewall. 

 

I doubt that is still the case today. I asked Diamondback about that measurement when I ordered from them earlier this year, and the whitewall measurement in the catalog (for wide whites that start at the rim) should be the visible part from the outside of the rim to the outside edge of the whitewall. My 2-1/4" tire mentioned above seems to back that up.

 

[buick man]

I remember reading/hearing something about how Diamond Back cuts (think router out) the sidewall of an existing black acquired tires from various tire manufacturers  to create the various white wall widths they offer as opposed to what an original factory produced manufacturer of a white walled series of tires would create via it's tire mold process.  Kind of like what folks back in the day could achieve by sanding/shaving down the black side walls of tires to underscore and expose the white rubber underneath. Oh and for most major 1957 car manufacturer jobs the design white wall mantra was thin compared to what the previous 56 and older "wide" white walls had been.  Chrysler with their completely new retooled bodies, even Ford, GM etc all went the route of the 2-1/2 look down considerably from the 3 and 4-inch www just the previous year.  Just take a look at factory photo promo shoots of these cars.  Buick even discusses the thinner white wall look in some of their advertising for 1957. Just a few thoughts and fact trivia picked up over time.

[highcking]

I'm probably going to go with the "American Classic Bias Look Radial" at $314 each. They have the "pie crust" sidewall. 

[Bloo]

43 minutes ago, buick man said:

I remember reading/hearing something about how Diamond Back cuts (think router out) the sidewall of an existing black acquired tires from various tire manufacturers  to create the various white wall widths they offer as opposed to what an original factory produced manufacturer of a white walled series of tires would create via it's tire mold process.  Kind of like what folks back in the day could achieve by sanding/shaving down the black side walls of tires to underscore and expose the white rubber underneath.

 

Highly doubtful. Most tires (for a few decades now) have no white rubber inside to expose. I believe the process they use is similar to recapping.

 

 

 

[Bill Stoneberg]

Diamondbacks are vulcanized to make various widths of whitewalls.  Read about the process here. https://dbtires.com/classic-car-tires/tire-making-process/

 

[highcking]

I admit they would look nice in the proper whitewall width. My question is whether this construction method will hold up to handling 5,000 pounds of Buick at 70mph. The old “retreads” would frequently fall apart, on both cars and trucks alike.

[JohnD1956]

19 hours ago, Bloo said:

 

Check with Diamondback about that. I think they can do almost anything, even triple stripe. I have a special-ordered 600-R-16 sitting in my garage with a 2-1/4" whitewall (2-3/4 is the narrowest in the catalog).

 

 

I doubt that is still the case today. I asked Diamondback about that measurement when I ordered from them earlier this year, and the whitewall measurement in the catalog (for wide whites that start at the rim) should be the visible part from the outside of the rim to the outside edge of the whitewall. My 2-1/4" tire mentioned above seems to back that up.

 

I measured mine this AM and there is 2 1/2 " whitewall showing.  

 

[old-tank]

9 hours ago, highcking said:

I'm probably going to go with the "American Classic Bias Look Radial" at $314 each. They have the "pie crust" sidewall. 

Ask for the date code on each tire.  That vendor often ships very old tires.  Radials are a perishable product:  5-7 years even if not used.  The Diamondbacks I bought were 3 months old.

Pie crust:  nice look, but harder to clean than the white walls. 

[avgwarhawk]

I like my pie crust crispy. 

 

[Ben Bruce aka First Born]

8 minutes ago, avgwarhawk said:

I like my pie crust crispy. 

 

 

 

 Yep and preferably with apples inside.

 

  Ben

[Dan O]

I just got a set of Coker Firestone repro's 8.20 x 15 with 4.25" white wall in bias ply for my '49 76s.  They are really skinny!  I also have a set of the American Classic Radials with pie crust for my convertible.  The radials look more like a modern tire but the Firestones have their own appeal with all that white plus the iconic Firestone logo.

 

I am a bit concerned that two of the Firestones have a bit of a curve to the face of the tire where it meets the road.  Not really flat at all.  Is that normal?  The radials did not.

 

Here's a photo of one just mounted.

[Bill Stoneberg]

10 hours ago, highcking said:

I admit they would look nice in the proper whitewall width. My question is whether this construction method will hold up to handling 5,000 pounds of Buick at 70mph. The old “retreads” would frequently fall apart, on both cars and trucks alike.

I have run them in my Electra for 5 years. I seem to go faster then 70 mph on occasion and loaded my car probably weighs close to 5,000 lbs. you figure they are built on a modern car radial tire that has to support modern cars with modern speeds.

[avgwarhawk]

11 hours ago, Bill Stoneberg said:

I have run them in my Electra for 5 years. I seem to go faster then 70 mph on occasion and loaded my car probably weighs close to 5,000 lbs. you figure they are built on a modern car radial tire that has to support modern cars with modern speeds.

I often sail along at 70-75 mph(dash buzzer starts getting angry) on Coker Classic bias.  No issue.  I also believe the materials to produce these tires today are better. Overall, the bias on the 60 runs very well. They do not track the road like the Universals do on my 54.   

[Matt Harwood]

On 11/18/2020 at 12:13 AM, buick man said:

I remember reading/hearing something about how Diamond Back cuts (think router out) the sidewall of an existing black acquired tires from various tire manufacturers  to create the various white wall widths they offer as opposed to what an original factory produced manufacturer of a white walled series of tires would create via it's tire mold process.  Kind of like what folks back in the day could achieve by sanding/shaving down the black side walls of tires to underscore and expose the white rubber underneath.

 

No. Diamondback adds a whitewall and vulcanizes it to the tire carcass after polishing the sidewall. They are not cutting the sidewall of the tires.

[60FlatTop]

In 20011 I installed these 8.20 X 15 Firestone Cokers on my '60 with the rear wheels glass beaded and painted along with the rear end as part of the u-joint job.

 

A few weeks later I mounted the fronts.

 

Those replaced the four like tires I put on in 2001. About 10 years and 12,0000 miles later, 2011.   My buzzer is set at 85 and I will hop on the NYS Thruway any time and roll with the rest.

This year I am ready to replace set #2. Wear and use are about the same. I put one tire to the rear last year as ot was wearing thin. I may change vendors this time because I want to go to an 8.00 X 15 with a 2 1/2" whitewall as original.

Edited November 19, 2020 by 60FlatTop (see edit history)

[Matt Harwood]

I think it is also worth mentioning that bias-ply tires are not inherently more dangerous than radials. They offer different ride quality and handling, but the differences are pretty subtle. The most notable difference is that radials eliminate that tendency to follow ruts and irregularities in the road and radials might be better at stopping, particularly when wet. My experience suggests that radials are quieter as they age, but that really depends on the tire tread as much as anything. I'm a fan of radials, I like they way they ride and handle and I use them whenever possible, but I do not regard bias-plys as a demerit on an old car and certainly not a safety concern (unless they're expired, which applies to all tires).

[alsancle]

We have this thread at least once a year.   My only question would be are the radials going to look stupid or have they started to make them look like bias ply tires?

 

 

[Matt Harwood]

41 minutes ago, alsancle said:

We have this thread at least once a year.   My only question would be are the radials going to look stupid or have they started to make them look like bias ply tires?

 

 

 

 

[alsancle]

I think a FAQ forum for the usual suspects.   This is definitely one of them.

[highcking]

The Coker Tire Company's views are here (from 2015):

 

https://www.hemmings.com/hmw/bias-ply-or-radial-tires.html

 

My own comparison and choice was between a genuine bias ply and the American Classic "bias ply look-alike radial." My only qualm about the latter was the whitewall width (too wide) vs. superior control and roadability of a steel belted radial. I've had steel belted radials on all my big cars over the years, including my '58 Buick Century, numerous Cadillacs, and my enormous '77 Mercury Marquis. As Coker points out, bias plies ride narrower with less road contact and have a tendency to "follow the seam" in badly-maintained roads, which is just about every road. To my mind, the only valid reason for putting on bias ply tires (other than slightly lower cost) is mechanical and cosmetic authenticity with the car leaving the factory. We all draw our own lines there. I balk at things like disc brakes and third stoplights, while other might find these are perfectly reasonable. My main worry on my '58 Roadmaster is, will the perfectly-functioning, non-leaking Flight Pitch Triple Turbine Grade Retarder Dynaflow stay healthy?

 

Bill in Luray