Bias ply Tries vs Radial tires

[blt2krl]

What are the differnces/ advantages of each on and off road? what do people on here like to run and why?

[maxrad]

All I know about the bias ply tires is that the people throughout the 3rd world and middle east use them instead of radials because they are cheaper and easier to manufacture along with being able to withstand desert temps and unimproved roads with more reliability. I believe the tradeoff is that they are not as smooth on improved roads.

[jdubGW]

Bias ply tires generally contain a softer rubber compound and wear out easier on road. They also, for some reason unknown to me, are harder to build truly "round". This makes for some interesting weight differences around the circumference of the tire, and makes them harder to balance.
Radial tires, because of the braided metal under the tread, are flat resistant and can contain more durable rubber compounds.
Bias ply is cheaper, and a lot of ppl like to run them offroad because of the softer rubber.
Hope I didnt muddy the water.
jdubGW

[dnixon]

you also get flat spots when you leave bias ply's sitting over night... the JP rag did a pretty nice little article on tires and rims this month check it out for some more info on the bias vs radial topic

[andy d]

radials track a lot better over the road. bias seem to have ruggeder sidewalls. that would make them a better off road choice in my eyes. btw, for the limited amount of beach travel i do, radials work fine

[Bombadier]

Ditto the JP article.....good stuff, even for a "little Jeep" magazine ;)

[PAJEEPER]

I like bias ply's for hard work. They have alot more plies than a radial and are cheaper. I've seen old bias tires still hold air even with big cuts in the sidewalls. Though I can't say much for swampers but the old style 7.50-16's and 9.50-16.5's are tough tires. I'll be running 7.50-16 bias plies on my J20.

The trade off is a little rougher ride but its a truck so I dont care much.

[BostonWagoneer]

Bias Ply:

The bias-ply tire is made of layers of rubber-coated plies composed of textile cords, usually nylon, placed upon each other at approximately 30-degree angles. These plies are then wrapped around the bead wires - which anchor the tire to the rim - to form the casing, or air chamber. The plies are then covered with more rubber to form the tread pattern.

Performance:

The only way to increase the strength of bias-ply tires is to increase the number of plies and bead wires. More plies means more mass, increasing heat retention, reducing tire life.
The bias-ply tire casing is constructed to form one working unit. When the sidewalls deflect, the tread squeezes in and distorts. This makes the tire scrub or squirm, decreasing traction, operator control and accelerating tread wear. Since the tread is subjected to any flexing that occurs, the footprint, or contact patch, distorts. This distortion causes abrasion from the ground surface, which reduces the life of the tire. All of these factors significantly increase fuel consumption.
Bias-ply tires have reduced life due to fast wear, high fuel consumption and reduced grip and control.

Radial:

The radial tire is constructed in two parts. First, a single layer of rubber-coated steel cables arch from one bead to the other to form the tire casing. Second, numerous rubber-coated steel belts are placed in the crown, under the tread, to form a strong stabilizing unit.

Performance:

To increase a radial tire's strength, larger diameter steel cables are used. These steel cables help reduce punctures, tears and flats. They also help distribute heat, resulting in a cooler running tire, improving fuel economy.
The combination of steel stabilizing belts and the single-layer radial casing allows the tread and sidewall to act independently. The sidewall flexes easily under the weight of the vehicle and its cargo, while the tank-track type tread provides even contact with the ground. Greater vertical deflection is achieved with radial tires. This is desirable because extreme flexing greatly increases resistance to punctures while protecting the operator and expensive vehicle components.
The stabilizing steel belts and radial construction minimize tread distortion. As the sidewalls deflect, the belts hold the tread firmly on the ground, minimizing tread scrub and greatly increasing tread life.
When negotiating curves and encountering side forces, the independent action of the tread and sidewalls keeps the tread flat on the road. This allows the tire to hold to its path.
Studies of highway use demonstrate the effectiveness of radial construction. Independent road tests* showed the radials made lane changes on wet pavement 10 percent faster; stopped in a 21 percent short distance; ran 27 percent cooler and negotiated curves 15 percent faster. These proven performance results are why trucks and automobiles use radial tires.
Summary

Summary:

Earthmoving equipment can achieve outstanding performance by using radial tires.

Radial tires for transport and working machines deliver longer life, have significantly fewer flats and provide better traction, all of which result in more uptime for machines compared to those equipped with bias-ply tires.
Other radial advantages include low fuel consumption, improved operator comfort and machine operation due to increased sidewall deflection. Radials also lower a machine's center of gravity, which improves stability. This results in more productivity from equipment on the job site.

http://www.michelingc.com/na_eng/News/85.html

[Stuka]

I have run both types of tires for some time.

Radial = ten times better for street, but thin sidewalls make them suck for back woods craling where you can poke a hole easy

Bias Ply = better for snow because of softer compound, *WAY* thicker sidewalls, tire is much more ridged, and generally can carry more weight. Big rigs and such still use Bias Ply's because they hold weight beter, and they can be retreaded for cheaper then radials.

EDIT: oh ya, with my bias plys I could run them down to 5psi and they would looks a little low on air. I could drive them on the street at 10psi without any problems as long as i didnt act like i was in a road race smile.gif My Radial's wont do that, at 10psi they look pretty flat.

[ February 23, 2003, 06:30 PM: Message edited by: Stuka ]

[Navajo]

I love TSL SXs, ride bad on the street, but tough as nails offroad!

[jdubGW]

Forgot to mention, dont ever mix radials and bias on the same vehicle. Because radials track so much more accurately that bias, if the steering input is extreme, one end of the vehicle tracks and the other gets "squirly".
jdubGW

[Navajo]

That makes it more of a challenge to drive!