Everything You Need To Know To Find The Best Tire Bead Wire

Did you know entry-level tire construction engineers, compounders and designers aren’t allowed to touch a new tire for a year or two? That’s because tire design and development isn’t part of any college curriculum. The making of a competent tire engineer isn’t the job of a college professor. That task belongs to veteran tire company technical types who serve as mentors.

Goto sft to know more.

That means only experienced engineers and chemists are making decisions about the tires you sell. These seasoned vets constantly make running changes in tire technology to improve such things as noise, vibration and harshness, as well as handling characteristics, tread life, braking, water dispersion, and even better gas mileage. And the process never stops.

In this article, the first of four, you’ll get a dose of “plain English” explanations about tire pieces and parts. Tire buyers count on you to explain the complexities of a tire. With all of the advanced technology we’ve seen in recent years, and all of the accompanying acronyms, we’ve lost touch with the basics. How, after all, can you explain to a customer why a tire performs as it claims if you don’t understand more than the acronyms?

A tire must not only look like it can get the job done; it must have the guts to perform the tough work it is asked to do. It must equal or exceed the design intention of every engineer who gives it life. And it must do so with its basic components: the bead, the sidewall, the belt package, the tread compounds and the tread design.

We’ll begin with a close look at the bead and sidewall areas of the tire. In future issues, we’ll address the other primary components.

The Bead Area

In the simplest language, the bead is a loop of high-tensile steel cable coated with rubber. Its primary mission is to provide the muscle a tire needs to remain seated on the rim flange and to pass along the forces between the tire body plies and the wheel.

Sometimes called the bead bundle, the bead must also be tough enough to handle the forces encountered by tire mounting machines.

Typically, a bead bundle is comprised of about one pound of large monofilament steel cords. The cord is coated with rubber and then wound into a properly sized loop based on the designed wheel diameter. The resulting bundle is then wrapped with a ribbon of rubber-coated ribbon material. Depending on the tiremaker or the product, the resulting bead hoop can be square, rectangular, octagonal or oval in shape.

Of course, it’s impossible to talk about the bead bundle without mentioning the tire’s body plies. Keep in mind that body plies run from bead to bead, looping down and around the bead bundle, which holds them in place.

In most cases, a passenger tire casing has one or two body plies, which can be made of polyester, steel or nylon. We’ll talk more about the casing later, but it’s important to note how the bead bundle fits into the overall tire design as it relates to body plies.

At The Apex

Next, let’s look at the bead apex filler – a hard or soft rubber compound that envelopes the bead and extends up into the sidewall. If the tire is a high profiler designed to provide a boulevard ride, the bead apex filler will be softer. However, on a low-profile ultra-high performance tire, the bead apex will be much harder and extend further into the upper sidewall area for added stiffness.

Generally speaking, a low-profile tire with a stiffer sidewall (and a harder bead apex filler) rides rougher but delivers better handling. A softer sidewall (with a softer compound bead apex filler) provides a softer, more comfortable ride.

Another function of the bead apex filler is to create a smooth contour for the body plies around the bead wire in the lower sidewall area.

The remaining component in the bead area is the bead chafer, or chafer strip. Its mission is to protect the bead area from rim chafing, mounting/dismounting damage and to prevent the tire from rotating on the rim. Chafer strips are made of a hard, durable compound rugged enough to withstand the forces working against it.

In quick review, the bead area of any tire is made up of a bead bundle, a bead apex filler and a bead chafer. Each has a separate job, yet each piece must rely on the other to function the way tire construction engineers intended.

The Sidewall

Now that we have the tire firmly attached to the wheel, the bead wire well protected, and the body plies safely wrapped around the bead, let’s move up to the sidewall.

Tire sidewalls vary in thickness from the shoulder area to the bead area. In the thinnest part, typically in the middle to upper area, most sidewalls are between 6- and 15-mm thick – about 1/4- to 5/8-inch thick. The differences are dependent upon tire application – thinner for ride comfort street tires (S- or T-rated), thicker for off-road light truck tires that require significantly stronger sidewalls.

You should also know that the sidewall and bead areas of a tire represent about 30% of a tire’s total weight. Multiple sidewall plies are typically a blend of natural and synthetic (butadiene) rubber.

Keeping that in mind, a sidewall’s primary mission is to transmit force from the ground to the vehicle via the wheel. Inflation pressure holds the sidewall out where it’s supposed to be, allowing it to help carry the load.

The sidewall is also responsible for maintaining lateral stability as hard cornering and/or braking forces are transmitted through the sidewall to the bead.

Engineering at Work

As these forces push and pull their way though the sidewall and bead area, we see some of the finest engineering in the world at work. The body plies, always under compression, are assembled in such a way that the forces working against them are passed to the vehicle via the strong contact between the bead wire, the chafer strip and the wheel’s rim flange.

All of this assumes that the tires are properly inflated. Driving on an underinflated tire results in unwanted sidewall deflection. Such deflection can be more than the tire was designed to handle, resulting in too much heat generating flexing and life-shortening possibilities for the tire over time.

Acceleration also does its best to shorten tire life. Step on the accelerator, and you pull the tire components forward, bending and twisting them in the process (If you’ve ever witnessed a rear drag race tire work in slow motion, you’ve seen an extreme example of this phenomenon.). Step on the brakes, and the forces at work stress the rubber in the opposite direction.

Ultra-high performance tires handle these assignments well because of compounding and design technologies employed in the tread area, which we’ll talk about in a future Tire Tech.

To be clear, it is the sidewall and bead areas that deliver all of the real performance and driver comfort.

Sidewalls also face another force: the elements. Weather and ozone can cause cracking and weather checking. That’s why a tire’s sidewall is loaded with a host of materials like anti-oxidants, anti-ozonants and paraffin waxes.

Bounce-Back Factor

The ideal bead and tire sidewall combination offers low hysteresis (for low energy consumption), good tear strength and low heat generation. These properties and characteristics contribute to low rolling resistance, which, in turn, contributes to better gas mileage.

In tire-speak, low hysteresis represents the ability of a tire to return to its normal shape after encountering severe deflection or opposing force. Think of dropping a super ball (low hysteresis) and a ball of Play-Doh (high hysteresis). The super ball bounces very high because it doesn’t absorb the energy. Play-Doh doesn’t bounce because it absorbs all of the energy.

The rubber used in tires must fall somewhere in between, yet be a lot stronger than Play-Doh. Its job is to absorb some of the energy, which is converted into heat.

A tire’s innerliner, one of the first building steps in the production of a radial tire and the last item we’ll talk about in this installment, functions like an inner tube and is the unseen part of a tire and its sidewall.

For more Tire Bead Wireinformation, please contact us. We will provide professional answers.

An innerliner is made up of low-permeability rubber laminated to the inside of a radial tire. Its mission: to keep air in the tire. Typically, it is made of butyl rubber, which is not reactive with oxygen. A small amount of rubber (synthetic isoprene) is added to allow the innerliner to adhere to the body plies during vulcanization.

In the next Tire Tech, we’ll explore the role of the belt package. If you require further elaboration on what we’ve talked about in Part 1, please drop me an at [ protected].

Mini Glossary of Basic Tire Terms

Bead: The tire part made of steel wires, wrapped or reinfored by tire cords and shaped to fit the rim flange. The bead anchors the body cords of the tire to the rim so that they may resist external and internal (pneumatic) forces.

Bead area: That part of the tire structure surrounding and in the immediate area of the bead wire hoop. Consists of fabric components and shaped rubber parts to provide a tight fit to the contour of the rim flange, resistance to chafing at rim interface and flexing support for the lower sidewall.

Bead filler (apex): A rubber compound filler smoothly fitting the body plies to the bead.

Bead heel: Rounded part of bead contour, which contacts rim flange where the flange bends vertically upward.

Bead reinforcement: A layer of fabric located around the bead area outside of the body plies to add stiffness to the bead area.

Bead separation: Failure of bonding between components in the bead area.

Bead wrap: Subsequent to forming of the bead, for some manufacturers, the bead is wrapped with a fabric similar to friction tape.

Body (carcass; casing): The rubber-bonded cord structure of a tire (integral with bead) containing the inflation-pressure-generated forces.

Body ply turnup (turnup plies): Ends of body plies in a tire, which are wrapped under the bead wire bundle and extend up the sidewall.

Chafer: A layer of rubber compound, with or without fabric reinforcement, applied to the bead for protection against rim chafing and other external damage.

Flange: The upward curved lip of a wheel rim, which contacts the outer surface of the tire bead.

Flex cracking: A cracking condition of the surface of rubber resulting from repeated bending or flexing.

Flipper: A partial ply wrapped around the bead coil but not extending the full height of the sidewall.

Innerliner: Innermost layer of rubber in a tubeless tire, which acts as an inner tube in containing the air.

Innerliner separation: Separation of tire innerliner from tire carcass, resulting in air loss.

Ply turn-up: The portion of body plies passed around the bead coil.

Sidewall: The portion of either side of the tire that connects the bead with the tread.

Hedge tree
Posted 11/8/ 11:26 (#)
Subject: Seating tire beads


Central KansasJust about wore myself slick this morning trying to remount a little bitty 14" radial on my '90 Ford Ranger. These are Sumitomo tires and if you want to pick up all the nails, wire and screws from your township roads...put these suckers on and you will get them all.

I have one of the little cheapie 'Ranger' manual tire changers that was recommended on this site a year or so ago......about $80 or so. It breaks these smaller tire beads fine and demounts them fine. I repaired this tire for about the 3rd time, mounted the bottom half on the rim, had a little trouble mounting the top 1/2 but slicked it up and it went on.

NOW......trying to seat that top bead on these aluminum wheels is the S#%*#!! I try straps around the circumferance, pounding on the rim to seat it with a rubber hammer, setting the tire on blocks and standing on the rim, just about everything I have seen except the DREADED ETHER and FLAME!!

So...tell me, is there a better way to get the bead to seat or I am plagued with a bad tire/rim combo here? Gotta be a better way. Of course, a $1,000 tire machine might help, but that ain't gonna happen.


Hagen Brothers farms,Goodrich NDBuy or build one of those air tank with a big ball valve and nozzle gadgets, to blow enough air into the tire to pop it onto the bead. Would not be without mine, it was build from an old portable air tank, a $10 ball valve and a few bits of scrap pipe.


Agent Orange: Friendly fire that keeps on burning.

Jon is right. If you trust your welding, you can build one. They also sell them, but are kind of pricey for what you get:

http://www2.northerntool.com/product/.htm

They do WORK! A couple years ago, Wane and I were mounting a brand new tubeless semi tire and an old gentleman who worked at a gravel/crushing pit happened to be visiting. He watched us mount the tire and when we got to the bead seating part, I thought I detected kind of a snide grin as he was watching to see us fight with getting the thing seated on the rim. I walked over by the compresser and grabbed my tank. Aired it up and seated the tire with one blast. About all the old gentleman could say is: "We're getting one of those!"

Tekonsha, MichiganYou can get twice the air into the tire with the valve core removed from the stem.


The Original Lock Springs Rver RatWe have mounted hundreds of tires with either,Large tractor tires,truck tires,and more. Works great and cost next to nothing.We also have set many a tire with either, just make sure you don't get a weak tire. That makes a big mess, and scares the $hit out of you. The only thing is you must be very careful. Considering buying a bead seater that you guys are talking about! May be worth the money to save an arm or leg! BE CAREFUL!Had a guy use that method on an ATV tire. Did it in a building without a ceiling and the rafters on 2ft centers. Tire got up into the rafters and took some time to fall out. Dust rained down for a good while....................

Never a vid camera around when you need one..................

Tim


Hagen Brothers farms,Goodrich NDThe cheetah is a nice unit, but WOW !! how do they justify the $370 price. Mine is kind of old and grody looking, but when I open the valve,the result is exactly the same. I suppose $5 for a rattle can of Krylon would help a lot ;- ) I think the ones with the valve / nozzle on the end are easier to control than the side mount type.

I wonder If the story I read is true, that you can't blow up a tire with ether because the ether runs out of oxygen and goes out before it generates enough pressure to explode the tire ?? I know when you drain one that has been bead seated with ether,there is still the odor of unburned ether.



(bead seater.JPG)



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bead seater.JPG (95KB - 414 downloads)
Thinking of building a cheetah also. Could you build one out of a 20# propane cyl? Have a couple old ones that a new valve would cost almost as much as a new bottle at sam's. Question is, just take old valve off and let it air out for a while before cutting/welding, or too dangerous to consider?


Hagen Brothers farms,Goodrich NDWho saw "myth busters " last night when they blew up a 55 gal electric water heater ??
They myth was that a water heater can blow up through and out the top of your house.
They took a new 55 gallon electric heater, removed the thermostat,high temp kick out and T & P valve, and set it in a little shack with the roof and ceiling built to California housing code, and turned on the power.
At a bit over 450 psi, the bottom of the tank blew out and demolished the house then went several hundred feet in the air. It took a long time after the explosion until that heater clunked back down to earth :- )

Kind of like this one I found on U tube. The myth busters explosion used a bigger heater and was much more impressive ;- )

http://www.youtube.com/watch?v=GF_Wrm-Ns0I

Edited by Jon Hagen 11/8/ 13:32


Wyoming

I imagine their cost of liability insurance is a significant component, as well as being a reason why we don't see competitors.

They do work, even on the big super-single balewagon tires. It took me 20 attempts with the valve stem removed, a fat air hose running 15 CFM/100PSI air into the tire and some pipe snot on the bead to get it to seat, but it did work. The rear tire on a ain't small - it is about four or five times the volume of a 265 16" pickup tire.

East Kansas, DeSotoFill it with water and burn your first hole with the electric welder for safety. GiffordI watched it, and all I can say is WOW! I had to rewind it, and watch it a couple times because I was laughing so hard. I would say that explosion, along with the rocket made from plumbing parts are the two coolest things they have done. Also the scariest, because it shows how simple it would be for any idiot to do it.

Edited by Matt NCOK 11/8/ 14:22


Le Sueur VIA St.ThomasI was cleaning sheds last spring wanted to demount tires to get rid of them. There was one tire completely rusted to an old split rim. It couldn't be demounted, even after removing the little band.

I took the tire out to the middle of the yard, placed it flat on the ground, ring side down, and hooked up an air hose to the tire. I went back in the shop turned the valve on to the hose and watched 'safely' inside the shop. It took a LOT of air. Based on the amout of fill time, it must have been at least 50PSI, when she went. That tire flew staight up about 15', spun a couple times in the air and landed in the original spot.

pretty cool, should have got video from that.

good luck -jimWe built ours out of an old 20# propane tank. cut the handle part off and the valve, weld on a pipe. Drill a hole in the top and use a coat hanger to pull a steel valve stem through. Screw on a valve and it's done.
I dunno if they even try to justify the price of the Bead Cheetah, but it really doesn't matter. They have you by the nads anyway. 'Here', if a department of Labor inspector happened into your shop as they are known to do at times and saw that 'cheetah' you have there, he'd have a hairy canary and start filling out paper. If it isn't an approved pressure vessle, in the sense that it was originally developed as a bead cheetah, you've got a problem.... That's a modified air pig, right?
I'd even be leary of admitting to having one or showing pictures....
I've seen them made from 20 pound propane bombs too. They work good most of the time.
I will say though that I have seen situations where the cheetah doesn't work. Those tires get packed with a LOT of Murphy's soap and they generally air up....

Rod


Leesburg, OhioCheata tanks really do work...on about any size tire from rear tractor down to lawn mower gauge wheels.

Yes, they are pricey. The reason is....LAWYERS!

SE PADave,
How'd you get the sucker on and off the rim? I assume you have some sort of tire machine, cause it took like 5 guys and a 6ft bar to get the critter back on the rim on the ..... all that after I ran a haybine reel tooth into the tread.....

Rodney


Whiskey, Tango, FoxtrotHave been taken out by reel teeth and those damn rake teeth with the little rubber on the end like the old darf rakes had. Those things are kind of a job security program for tire manufactures. We always manage to find them with a nice expensive balewagon tire as well.


Hagen Brothers farms,Goodrich NDNot much problem here with a farm shop and no employees. Never had an inspector check anything except electrical wiring.

If we had a couple hired hands in the shop and using my shop built tool,then I can understand where there might be a problem. I hope to never have to deal with that, I like being a little two man farm operation.

Yep, the thing is built from a 30 year old TSC portable air tank.

West Union, IOWA FLOLO Farm I've used the cheetah many times, but I'm looking at making a different version and figured run it up the flag pole here.....

What I'm looking at is using a 2" NH3 hose (PSi rating of 600# ) about 20 foot long and put the 1.5"valve and nossle on the end (with a chain and hook for saftey ) I haven't taken the time to figure volume but length of hose could vary to accomidate. Biggest fear I've had would be if the hose would get away under pressure, though it should be momentarily, could still whip thus the chain. Biggest plusses I've thought of is no welds to worry about like mentioned above and a little easier to handle.

What does everybody think of that +/-

Priced it before harvest and if I remember $200 would put it all together at FDS--loranget the video cam going if it gets loose

Wyoming

This was on a tire that had simply gone flat and de-beaded over the winter -- I didn't have to take it off the rim (or put a new one on ).

Turned out that there was some crap in the bead that caused a slow leak. A little spiffing up with a scrubby sponge and it was fixed.

Getting the bead back on, tho... it was an experience, even with the bead cheater tank. I tried the ether trick a couple times, but it doesn't work worth a crap when the tire is still on the axle. The bead cheater tank did work tho, with a binder strap around the circumference of the tire smack in the middle of the tread face to make the sidewalls "pooch" out a bit onto the rim.

Brazilton KS

I think, no I know a 1" hose is extremely difficult to hold onto with 140 psi. About the only way to do it is to straddle it and hold on with both hands.....but that has it's own set of disadvantages. If you think about it just a second or two I bet you can figure them out. Once will be enough for most reasonably intelligent men.

You don't have enough money to get me to try to hold onto a 2" hose.

Take a piece of 1 1/4 pipe and slide a piece of 1 1/2" thin conduit over it with stops welded to each to keep them from telescoping clear apart. Screw it into two 90o street els to make a gooseneck joint and screw that into a 1 1/2" valve (a N/C deadman valve would be very nice ) in the 2" shop air main about the right height so that the telescoping tube will reach down to about 4" from the floor, up to about 2' from the floor. Leave the theads loose enough that they will move, but not so loose that they will move freely. Now you have a fixed pipe which will adjust down against the top bead of the tire which you have laid on the floor beneath the apparatus. Wear ear plugs. It will beat the heck out of a cheetah because it doesn't run out in 3 seconds.

Edited by plowboy 11/8/ 20:42
Tim in WI
Posted 11/8/ 21:10 (# - in reply to #)
Subject: Have one of those


Embarrass WI

I bought a similar one off ebay a couple years ago. Works good, has saved my bacon several times. I get to re-seat skid steer tires pretty regularly.

This one comes from a Californicater, the one I have, IIRC, came from a Hoosier.

http://cgi.ebay.com/ebaymotors/BEAD-SEATING-SEATER-BLASTER-TIRE-CHANGER-AKA-CHEETAH_W0QQcmdZViewItemQQcategoryZQQihZ004QQitemZQQrdZ1QQsspagenameZWDVW

The company is the world’s best Polyester Liner Fabric supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

RodInNS
Posted 11/8/ 22:52 (# - in reply to #)
Subject: RE: Seating tire beadsHope I never have a problem either.... Mine is of the propane bomb fame.
Same situation here. Onle me and the old man, so the law mostly stays away. That part of the law does anyway, but I do know of guys running shops that got nailed for that very thing.

RodSchool Of Hard Knock
Posted 11/8/ 23:51 (# - in reply to #)
Subject: RE: Seating tire beads

Central NDI also have a homemade bead cheata. I made it out of an auction sale bargan$12 tank that was fitted with a plate and designed to use compressed air out clean engine air filters. It is simmilar to the bead cheat you purchase.WORKS GREAT!! I am wondering though if you couldnt use a hose right from your air compressor. I have 1" lines in my shop and on the end I have a large ball valve to drain moisture.Let me tell you it lets out a LARGE amount of air at once. If makes you deaf and the cats run for cover so fast you cant see em run in the dust!.Feels like it could blow your ears and shop windows too.
I think if I put3/4 inch or larger hose on the end and directed it in the bead while the air line is on the valve of the tire it would seat the bead.Rich
Posted 11/9/ 01:26 (# - in reply to #)
Subject: Ok, Hedge, Other options less pricey and safer.......


KansasThat Cheetah is ridiculously high priced. I use ether (NOT either.....It's ether, guys ) but it is not something to advocate to people that are not experienced with it.

Here are a couple cheap tricks.

1: Go buy murphys oil soap. That thick brown goop. Place it all around the bead between the tire edge and the rim. It will act as an air barrier till the tire fills up and places the bead against the rim edge, also, a lubricant to eliminate that "Boom" when some of those beads develop a sticky spot and need 80 psi to convince them to get over to the edge where they belong. Once tire has aired up scrape all the oil soap back up and place back into container for future use.

2: Mix dishsoap.......dawn, ajax, whatever, with water and use that as a tire lubricant. Smear it all around the beads then I take my foot and push as hard as I can in the center of the rim while pulling back on the tire. This places one side into the bead as far as one man can make it go. Now, let it set a bit. (Works best on warm arid days ) after the water has evaporated a bit. Pick the tire up and set the rim over the top of a 15 gallon barrel or something with a smaller circumference than the rim. Gently lower the other side of the tire down after the rim is resting on top of the barrel and then hit the air to it and it will more than likely hold on the top side, the bottom will reach enough to make a seal and walaa......taking air.

As another suggest above. make sure that valve core is removed. So much more air can enter faster that way.

I can tell you that trying to tie a rope down the center of the tread and forcing the sidewalls outwards is a joke. BTDT. Ether works too but if you are really set on doing it that way go somewhere where someone has experience doing it and watch them very carefully. There is a trick to it.

Personally, I always did like that coats tire changer there at Shambergs station. Pull the tire up, hit the pedal to the floor and while air was going in the valve stem from the hose you locked on, 4 air holes in a pipe underneath shot air up into the space between the rim and the tire. Same theory as a cheetah except 1 big pipe vs. 4 outlets around the big pipe.

Murphys oil soap. Go buy a big jug of it. Any person that spends any amount of time ding donging around with tires should have it.

Edited by Rich 11/9/ 01:28
pbutler
Posted 11/9/ 08:11 (# - in reply to #)
Subject: RE: Ok, Hedge, Other options less pricey and safer.......


Macon, IL>>I can tell you that trying to tie a rope down the center of the tread and forcing the sidewalls outwards is a joke.<<

Actually I have had good luck with that on smaller tires-on bobcat and wagon tires.plowboy
Posted 11/9/ 08:43 (# - in reply to #)
Subject: RE: Ok, Hedge, Other options less pricey and safer.......


Brazilton KSThe tire machine is great on ones which are going to take but it's nothing like the 1 1/2" pipe.
loran
Posted 11/9/ 08:59 (# - in reply to #)
Subject: Re: Seating tire beads

West Union, IOWA FLOLO Farm Thanx for the idea Plowboy, the reason it hasn't got put together yet is the idea of the hose whipping. I've handled a 12 gallon seater enough to know it's almost a 2 man job, I guess we'll see what this winter produces in the shop--lorantmrand
Posted 11/9/ 09:09 (# - in reply to #)
Subject: Re: Seating tire beads


Southeast ColoradoThe guy that invented the cheetah is from my home town. Doing pretty well for himself now. Moved to a much ritzier neighborhood! Kind of cool though that he use to be a BTO hired man.ronm
Posted 11/9/ 10:23 (# - in reply to #)
Subject: Re: Seating tire beads

Fruita COHere's my solution-throw it in the back of the pickup & haul it down to CO-OP, come back an hour later, pay the man & take it home-life's too short to be d*ckin' around w/tires when there's people who do it for a living...I realize not everybody's as close to a tire shop, but it hurts my back to mess w/the dang things, I hate 'em...Rich
Posted 11/9/ 13:02 (# - in reply to #)
Subject: Bigger and Better.......


KansasAnd ether will whip that cheetahs hinekein....shade
Posted 11/9/ 19:15 (# - in reply to #)
Subject: Mount the TOP first.

NC KansasNot exactly sure what you are calling the "Bottom" and "Top". You should mount the side of the tire that has the Valve stem first. If it's stuck down on a center mount tire machine, grab the tire and pull up about 180 degrees apart and stick the top bead. Stick the air to it with the core removed, then you can push down a little near the tread and it will usually seat the bottom bead. Pay attention to the dish of the tire. Mount the bead closest to the deepest dish first. Murphy's works good too.

Sounds like you had the bead stuck furthest from the dish/valve core. Always makes it a lot tougher than it needs to be.

Good luck!plowboy
Posted 11/9/ 20:49 (# - in reply to #)
Subject: Re: Seating tire beads