Tire age? Bias ply...

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Originally Posted By: eljefino
Originally Posted By: javacontour
(I went looking for the name and came across this interesting 1976 issue of Popular Science, https://books.google.com/books?id=CgEAAA...mid&f=false)
I went cruising for tire names listed in this thread and found an ad in google news from the mid 70s. Tires were $50-70, then, and a buck was worth more! They also wore out faster.
When I bought my very first car in 1979, the first thing I had to do was buy a set of new tires, otherwise, my father would not let me drive it. So, father and son made the long journey to "Sears" where I purchased a set of brand new "Sears" brand bias ply tires for two reasons. 1. According to my Dad, they were "solid as Sears," (remember that one?) 2. They were on sale. Mounted, balanced and out the door was 200 dollars for four tires. That's when I was working at Walt Disney World and a 40 hour work week gave me a paycheck of $111 dollars. So, almost two full weeks to pay for them bad boys which, by the way, were bald as a babies behind at 12,000 miles. That, however, is another story.
 
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Originally Posted By: GreeCguy
Originally Posted By: eljefino
Originally Posted By: javacontour
(I went looking for the name and came across this interesting 1976 issue of Popular Science, https://books.google.com/books?id=CgEAAA...mid&f=false)
I went cruising for tire names listed in this thread and found an ad in google news from the mid 70s. Tires were $50-70, then, and a buck was worth more! They also wore out faster.
When I bought my very first car in 1979, the first thing I had to do was buy a set of new tires, otherwise, my father would not let me drive it. So, father and son made the long journey to "Sears" where I purchased a set of brand new "Sears" brand bias ply tires for two reasons. 1. According to my Dad, they were "solid as Sears," (remember that one?)
The stuff that Sears sold under their brand names was hit or miss. They don't make a single thing, although some of what they sold used to be top notch. My mom worked for a company that supplied Sears with some of its paints and their house brand dishwashing and laundry detergents. It frankly wasn't that great, but my mom could get that stuff cheap. If any friends/relatives needed paint, she could get it cheap too. We still had a stockpile of laundry detergent that lasted us for three years after the company moved and my mom found a new job. I suppose the big thing Sears had was that they stood behind the stuff they sold, and they had a strong history where one never doubted that they'd be around financially to stand behind their products. These days one worries about whether or not they'll go the way of Montgomery Ward (which also had auto service).
 

JHZR2

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Originally Posted By: CapriRacer
Also, I think those tread patterns were very typical of what tires looked like back then.
So what was the reasoning behind treads like that? I get it that tires today also often have a circumferential rib around them, I think its for ride quality or smoothness. But whats with all the cur outs in the ribs like that? Nowadays we sipe tires. I get that. Were these old-school sipes?
 
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Originally Posted By: JHZR2
Originally Posted By: CapriRacer
Also, I think those tread patterns were very typical of what tires looked like back then.
So what was the reasoning behind treads like that? I get it that tires today also often have a circumferential rib around them, I think its for ride quality or smoothness. But whats with all the cur outs in the ribs like that?
Technology advances and understanding about the science changes. I remember seeing some photos of cars entered into a competition for the sleekest car body design in maybe the 1920s. Many had variations on teardrops, but one actually had flat surfaces perpendicular to the ground. Of course we'd understand these days that having jagged edges like those on the major channels interferes with water evacuation (disrupts laminar flow). However, my current tires actually have these little ridges on the edge of the channels - ostensibly to help hold onto snow, which helps when driving on snowy roads (snow sticks to snow to some degree).
 
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Originally Posted By: JHZR2
Originally Posted By: CapriRacer
Also, I think those tread patterns were very typical of what tires looked like back then.
So what was the reasoning behind treads like that? I get it that tires today also often have a circumferential rib around them, I think its for ride quality or smoothness. But whats with all the cur outs in the ribs like that? Nowadays we sipe tires. I get that. Were these old-school sipes? Image deleted.
Bias tires did not wear as well as radials and the more chopped up a tread pattern was, the faster it wore. Circumferential grooves (and ribs) was a good compromise between wet traction and long wear. Having incomplete sipes (that is, sipes that do not go to the edge) is a way of getting a bit more wet traction, without sacrificing much wear. That kind of thing is still done today.
 
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You couldn't (easily) have "Cross treads" on bias plies, the tread ribs helped hold the shape. When radials came out, the ability to have cross treads allowed for "all season" tires as well.
 
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Bye
Originally Posted By: CapriRacer
I talk about tire sizing here: Barry's Tire Tech - Tire Sizing A lot of those tires in the playground are AlphaNumeric bias ply tires. That sizing system had a brief life span in the late 1960's and by the late 1970's had been replaced with the current sizing system. The date codes on the tires aren't much help as they are 3 digit with the year being only the last digit, with no decade mark. In order to get more exact than that, we need some insight into the tires themselves. Also, I think those tread patterns were very typical of what tires looked like back then. Best guess, those tires are from the 1970's.
Alphanumeric tire sized were used to at least 1979...my Caddy (LR78-15, IIRC) and a 1979 Skyhawk (D78-13) both used those sizes on the door tag.
 
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Da Swamp
Originally Posted By: GreeCguy
Originally Posted By: eljefino
Originally Posted By: javacontour
(I went looking for the name and came across this interesting 1976 issue of Popular Science, https://books.google.com/books?id=CgEAAA...mid&f=false)
I went cruising for tire names listed in this thread and found an ad in google news from the mid 70s. Tires were $50-70, then, and a buck was worth more! They also wore out faster.
When I bought my very first car in 1979, the first thing I had to do was buy a set of new tires, otherwise, my father would not let me drive it. So, father and son made the long journey to "Sears" where I purchased a set of brand new "Sears" brand bias ply tires for two reasons. 1. According to my Dad, they were "solid as Sears," (remember that one?) 2. They were on sale. Mounted, balanced and out the door was 200 dollars for four tires. That's when I was working at Walt Disney World and a 40 hour work week gave me a paycheck of $111 dollars. So, almost two full weeks to pay for them bad boys which, by the way, were bald as a babies behind at 12,000 miles. That, however, is another story.
Maybe my memory is faulty and I paid $100 for a pair of tires in '82.
 
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I remember a little bit about the tires my dad used from my childhood too. I think his cars bought new in the 70s both came from the factory with bias ply or bias belt, as I remember the take-offs of the older car in the garage, and of the later car, a pair mounted on steel wheels. Presumably, the "summer" rear tires. That car was a Chevette and spent very little time with us, as it was extremely unreliable (I remember every other morning a mechanic from the local GM dealership had to come over to try to get it to start). Car was probably ditched with the "snow tires" on the rear wheels. The next vehicle, a Datsun pickup, was the first of his vehicles that came with radial tires from the factory. I even remember what they were - Bridgestone RD113. I too remember looking at the playground tires, but that was so long ago in my past, I really don't recall anything other than I remember seeing the Firestone name. Other old tires, I remember the "snow tires" for the pickup, only on the rear wheels, were Sears Roadhandler Ice & Snow. The neighbour across the street had some kind of Uniroyal snow tire, which I remember the pattern of, because they resembled interlocking + signs, and were distinctly different from the other snow tires of the era. Mind you the Sears tires were for another reason, in that I remember they had fine sipes similar to what you would see on a modern winter tire.
 

JHZR2

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Originally Posted By: CapriRacer
Originally Posted By: JHZR2
Originally Posted By: CapriRacer
Also, I think those tread patterns were very typical of what tires looked like back then.
So what was the reasoning behind treads like that? I get it that tires today also often have a circumferential rib around them, I think its for ride quality or smoothness. But whats with all the cur outs in the ribs like that? Nowadays we sipe tires. I get that. Were these old-school sipes? Image deleted.
Bias tires did not wear as well as radials and the more chopped up a tread pattern was, the faster it wore. Circumferential grooves (and ribs) was a good compromise between wet traction and long wear. Having incomplete sipes (that is, sipes that do not go to the edge) is a way of getting a bit more wet traction, without sacrificing much wear. That kind of thing is still done today.
So then those "feature" cast into the circumfrential ribs would be considered "sipes"?
 
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Originally Posted By: JHZR2
So then those "feature" cast into the circumferential ribs would be considered "sipes"?
Yes, and I think the sipes originally went to the edges of the grooves and what we are looking at now is what they look at when worn. Today's tires do the same thing.
 
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Southwest Michigan
While attending college I drove a 1973 Pontiac Ventura with whatever was the cheapest bias ply tire was available when I got a flat: Power King, Atlas, etc. Once I got a used radial for free, but one road trip in the winter enlightened me to the fact it didn't play well with the bias ply tires.
 
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