Bias Ply versus Radial

[buick4547]

Well, this is the spring I replace my 15 year old tires on my '39 special..  I'm debating bias ply versus radials.  I have bias ply now.  Which do others prefer, and what are the pitfalls in switching to radials?

[Matt Harwood]

Radials. No contest. There will be those who will post below me saying, "It drove fine when it was new on bias-plys, I never had any problems with them, your car was made for bias-plys and radials will break it, radials aren't correct, you'll lose points in judging, etc," but the bottom line is that if you like to drive your car and don't show it competitively, radials simply work better in most situations. More comfort, better handling, and safer braking (especially in the wet). Some will say they don't like how radials look, but here's my '41 Buick sitting on radials. Can you  even tell?

 

 

Do a search on this forum for more information. Or search my name, I've long been a proponent of radials and have documented my many bias-ply failures and radial successes on this forum. My preferred vendor is Diamondback. My credentials are that I buy 10-12 sets of tires a year and unless I can't get a radial for my application, I go with radials every time and have never had complaints. I have, however, had complaints about a bias-ply that I put on a car and it made the handling "squirrely," and the bias-plys I put on my '29 Cadillac are pure junk (there is no radial equivalent for that car).

[Bloo]

Radials if you intend to drive it.

[Thriller]

Tell us how you really feel Matt ???

[Ben Bruce aka First Born]

Radials. And unless you MUST have whitewalls, go to your local tire store of choice and buy from them . Probably half price or less versus any of the "classic" stores.  Get the narrowest [  215?] and tallest [ 75 ? ] that will come closest to your original tire height..

 Would not have anything else.  

 

   Ben

[Dynaflash8]

Bias Ply look far better, but drive far worse.  I don't understand why Matt's Limited doesn't show a bulge at the bottom.  I opted for radials for my 41 Roadmaster after much discussion and thought.  The car drives 200% better than the 41 Roadmaster 4dr convertible I had a several  years ago.  But even with 40 pounds of air there is an ugly bulge where the tire meets the road.  I truly dislike the look.  But, I'll say this, I had my Roadmaster rolling down a rough road at 60 today on a test run and it ran straight as an arrow.  The 4dr convertible had bias tires and on that same stretch it jerked all over the road because of the ridges.  I can't think of the name.  I want to say Lincoln Highway tires, but I think it's the company the sold out to.  I'll post a picture of my sedan and you see if you can see the bulges.  I have the new hubcaps on now.  I've worked on the car for two weeks (I can only do one thing a day at my age..ha) to try and make it look more respectable for a Classic Car Club local tour with all those Cadillac's and Packard's.

 

Edited February 2, 2018 by Dynaflash8 (see edit history)

[29hupp]

I was asking the same question the other day and had an extremely knowledgeable person in the tire business tell me that for some reason radial tires dry rot  10 times faster than bias tires.  Has anyone else heard of this?

[Dynaflash8]

4 minutes ago, 29hupp said:

I was asking the same question the other day and had an extremely knowledgeable person in the tire business tell me that for some reason radial tires dry rot  10 times faster than bias tires.  Has anyone else heard of this?

Oh yes, life expectancy on radial tires is said to be 6-7 years.  But a friend who managed a Firestone store for 30 years tells me it is because the steel bands get rust from condensation and the rust weakens them.  I have no idea, I'm just saying..................

 

And also, in those pictures I just posted, I don't see the bulge, but boy I see it when I'm next to the car.

[Matt Harwood]

10 minutes ago, Dynaflash8 said:

Bias Ply look far better, but drive far worse.  I don't understand why Matt's Limited doesn't show a bulge at the bottom.  I opted for radials for my 41 Roadmaster after much discussion and thought.  The car drives 200% better than the 41 Roadmaster 4dr convertible I had a several  years ago.  But even with 40 pounds of air there is an ugly bulge where the tire meets the road.  I truly dislike the look.  But, I'll say this, I had my Roadmaster rolling down a rough road at 60 today on a test run and it ran straight as an arrow.  The 4dr convertible had bias tires and on that same stretch it jerked all over the road because of the ridges.  I can't think of the name.  I want to say Lincoln Highway tires, but I think it's the company the sold out to.  I'll post a picture of my sedan and you see if you can see the bulges.  I have the new hubcaps on now.  I've worked on the car for two weeks (I can only do one thing a day at my age..ha) to try and make it look more respectable for a Classic Car Club local tour with all those Cadillac's and Packard's.

 

 

Looking good, Earl! What kind of tires did you end up with? Are those the Cokers?

 

PS: Don't worry about what the other guys think--they're only going to see the back of your car anyway!

Edited February 2, 2018 by Matt Harwood (see edit history)

[Dynaflash8]

9 minutes ago, Matt Harwood said:

Looking good, Earl! What kind of tires did you end up with? Are those the Cokers?

Matt:  Coker was running a real deal around Christmas and I opted for them.  The car came with narrow ww Toyo radials.  It ran smoother with those tires..................   Just saying............    But it runs pretty smooth with these too.  I did all sorts of measuring and we found that 820R15 were exactly the same width as 7.00x15.  I didn't want to go wider because I'm going to put skirts on it.  They are being retored and painted now.  I'm probably going to get it painted.  The guy has agreed to sign a contract stating he'll have it done in a certain time.  No more jackleg painters for me fiddling for 3 and 7 and 9 years.  The pain remains after the good hourly rate is forgotten.  I don't have enough life left to wait them out.

Edited February 2, 2018 by Dynaflash8 (see edit history)

[Bloo]

There is a lot of wishful thinking on this subject. Bias does look better. People seem willing to accept any argument that bias is better, because they want that look. I want that look too. I am currently driving on bias.

 

People will tell you radials fall apart after 6 years (how does the rubber know?) and, that they will crack your rims, throw your hubcaps off,  and so on. There is a grain of truth in this last bit. You go around corners faster when the tires aren't trying to throw you in the ditch every 10 feet. It is also nice to be able to stop. Radials are even better if you can get rid of the inner tubes. Not all rims will work tubeless.

[Matt Harwood]

Here's an article I wrote for a CCCA publication last year:

 

Bias vs Radial.pdf

[Morgan Wright]

I want tires that ride better and are safer. I can't see my tires when I'm driving, they can look like steaming piles of compost for all I care. 

[West Peterson]

There is no need for radial tires on a prewar car... unless you want to be replacing your tires every 5 years or so. The benefits one gets from radial tires is more beneficial on the newer suspension technology seen on postwar cars. Also, your Special probably has a top comfortable cruising speed of 60mph (if fitted with a Century gear set), a speed you probably wouldn't want to be at for great lengths of time.

If your car is having troubles keeping a straight line going down the road, I suspect that you may have a need to rebuild your front suspension and/or steering box. King pins, tie rod ends, steering links, bearings, etc.

[Stooge]

Good read Matt! 

 I have used Diamondbacks on some off topic cars with larger diameter wheels and have been very pleased, I believe they were toyo proxes with the white wall. great tire and rode very nice for a good price.

 

For my '37, im still a little up in the air for which direction to go with, in regards to Bias Ply or a bias look radial at the minimum.

What is the consensus on the few options for radials that have the bias look to them? I was planning on a black wall for my 37 , but still want them to be aesthetically pleasing. i haven't had much experience with Coker, although i have heard they are better than they were a few years ago, but still for every positive, i read just as many negatives.

 

Has Diamondback ever released the Auburn tires? all i can find is them hinting at them for 4+yrs and then releasing one size for stock

Edited February 2, 2018 by Stooge (see edit history)

[Daves1940Buick56S]

Yeah, this is a topic that can go on forever, like what kind of oil. But I'll just throw in what I did - I ended up staying with bias, although tubeless. I really wanted a wide whitewall plus I wanted something very close to the original tire height of almost 29". I know the dangers of bias ply, heck I drove on them the first 10 years or so that I had cars so I know the pitfalls. You have to mentally drive well ahead of the car and be on top of the situation, a skill that we seem to be losing in this age of pushbutton automobiles and mindless driving where you can have adaptive cruise control, automatic lane keeping, accident avoidance, etc .

 

But frankly, with our old cars actually driving them in a highly focused manner is something that we should be doing anyway with our less effective brakes and mushy suspensions. So no, I am not taking corners fast or going much over 55 mph or even driving much in the rain. Given that, using bias ply tires to get the look I want is a reasonable tradeoff.

 

Cheers, Dave

[Dave39MD]

I replaced very old bias on my 39 Chevy with bias and it was a significant improvement just going from old to new. The car drives, rides and stops fine. It is HPOCF with 106k so  I don't push it very hard.

Edited February 2, 2018 by Dave39MD (see edit history)

[Brian_Heil]

Sort of related. I went 5.00 x 24 balloons on my 1923 from the 33 x 4.5 high pressure tires that it came with and I went through two sets of high pressure rears way too quick too. 

 

Night and day if you tour your early car, go balloons.  Twice the tread life too. 

 

I also have twice the contact patch between me and the roadway.  Important when you only have rear brakes. 

 

(Have been running radials on my 1957 and 1965 non Buicks that get driven also, for decades. Night and day. No, the tires are not decades old). 

 

 

Edited February 2, 2018 by Brian_Heil (see edit history)

[J.H.Boland]

I replaced the very old,hard,cracked Coker bias plys on my original '40 Packard coupe with Coker radials last year and so far am very impressed.The Packard rides and stops well anyway,but the steering stability ,ride and handling are noticeably improved. Six months after fitting these,the Diamondbacks became available. I hope I don't set off anyone's anxiety triggers by mentioning a Packard on a Buick forum.I do have three Buicks to one Packard.

 

Jim

[Buicknutty]

 I'll add to the chorus here as well. I have Diamondbacks on my '41 Roadmaster and love them. I originally started driving with radials a few decades ago on my '56 Roadmaster, and was hooked after the first day driving. These were Goodyears, and were OEM on some Cadillacs, as they had a widish whitewall, something like 1 3/8 or so. Looked decent on my '56, as I could not find real wide whites here in Canada for love or money at the time. The shop that put them on promised to replace them if I was unhappy with how the car drove. Needless to say, I never went back to take them up on their offer.

I have found that after 10 years or so, they tend to start to get aged, and show cracks in the sides, then they get replaced. I still drive this car quite a bit, and never push tires too far. I do live in a cold climate, and the car spends most of its' non driving time in the garage, which limits uv exposure.

 Keith

 

[Brian_Heil]

 

And a reminder to watch those DOT date codes and to ask (before you buy) what the codes will be on the tires coming on the UPS truck.

 

My previous post on DOT codes and buying old 'new' tires:

 

 

Edited February 2, 2018 by Brian_Heil (see edit history)

[Morgan Wright]

My '40 special rides on Goodyear LS2 Eagles with tubes. Almost the exact same size as 6.5 x 16

 

Less than half the price of Coker

 

 

 

Edited February 4, 2018 by Morgan Wright
Remove disparaging remarks toward vendor (see edit history)

[61polara]

I replaced the 18 year old bias ply tires on my '60 Buick last year with a new set of 8.00 x 15 bias ply tires just before a 4 hour drive to a AACA National Meet .  Drove wonderfully on Interstate and old US highways.  It was a great driving experience.  The old bias ply tires showed limited ware but were just starting to crack around the white walls.  Radials would have been trash after 5 years based on what I have seen on my other cars.  Old radials are the only tires I have owned that would through the complete tread when they got to be about 8 years old.  Unless you are driving your car 20,000 miles a year, I would stay with the bias ply.

[61polara]

"I want tires that ride better and are safer. I can't see my tires when I'm driving, they can look like steaming piles of compost for all I care. "

 

If you read Matt's article, you will find that he says both ride well and there is not a safety issue between radials and bias ply tires.  He believes there was a manufacturing defect in the bad bias ply tires he had.  Many radials have been recalled over safety issues over the years as well.

 

[buick4547]

Thanks  to everyone for their response to my  original post.  The bias ply tires  I  have now really haven't given me many problems, and other than catching them in a crack in the road from time to time, I haven't had much in the way of handling problems.  And as some have said,  a prewar car like my '39 really does have to be driven with some care and alertness.  I don't drive it much faster than 55-60 MPH, and I'm always conscious of who and what is around me.  Rarely am I on an interstate highway, and I would be avoiding interstates whether I had bias ply or radials.  

 

I think 61Polara,  Daves 1940 Buick 56,  and West Peterson have convinced me to stay with bias ply.  And as a final thought, I never thought about the radial bulge that results from using radials.  I don't like that aesthetic  problem.