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Setting tire bead

When you folks set a tire bead, do you first remove the valve needle? What psi do you set the compressor to for this job?

I always remove the valve core when setting a tire bead.

This allows the most volume of air into the tire when attempting to seal the bead against the rim.

It’s not pressure that seals the bead, but the volume of air.

The last time I replaced the tires on my truck, it took one of these to get the beads to seal.


Yes. It makes seating the bead a LOT easier

I use the tire mounting machine at work

But I seem to remember reading you’re not supposed to exceed 40psi to seat a bead

If the rim and tire are clean and properly lubed the bead can be seated with the valve stem installed but when mounting a tire it is much quicker to leave the valve out when opening the valve on the ring that throws the tire onto the narrower side of the raised rim.

Long ago when air powered Coats machines were rare and mounting tires required a great deal of elbow grease and sweat all manner of tricks and gimmicks were used to expand the beads out onto the edges and leaving the valves in didn’t make any difference. And for the DIYer I can’t think of any reason to remove the valve to mount a tire. For the DIYer bringing back the tricks is necessary. A ratcheting strap tightened around the center of the tread would likely expand the sidewalls far enough to make contact with the raised part of the rim where air pressure can build and push the beads out fully.

Roadside replacement of truck tires is often accomplished using a shot of starting fluid and a match quickly struck and dropped. But that’s not for the timid or inexperienced.

[quote=“Rod_Knox, post:4, topic:108035”]
Roadside replacement of truck tires is often accomplished using a shot of starting fluid and a match quickly struck and dropped. But that’s not for the timid or inexperienced.
[/quote] Some of the roadside guy’s also used diesel fuel for lubrication.

Back in the ‘Old Days’ when trucks had tube type tires and 3 piece rims with boots talcum powder was used and airing up a newly installed tire could be a life and death experience. I changed a few truck tires back then and developed a paranoia of the ring being tossed by the truck next to me on the highway. Cut throat shops would reinstall kinked lock rings and hope there wasn’t a problem.If there was it could be serious.

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Yes I recall those those type of wheel’s I also developed a very health’y respect of them the very few I did myself I used two heavy duty log chain’s for airing up after the wheel was back on the truck.

@Rod_Knox As far as the old type wheel’s go they have been outlawed for year’ now by the DOT but with one exception the trailer’s that haul container’s are still legal.

I worked at on\a class 1 common carrier until 1983 with a 40 bay terminal and a 5 Bay shop capable of holding 5 tractor trailers or about 15 tractors. We had 8 mechanics and one tire guy who did nothing but mount tires. The shop manager caught him inflating tires outside of the newly required cage and was chewing him out. at that very moment the split ring let go and went right through a cinder block wall. The only thing that saved our tire guy was that he had made a tire inflator long enough to inflate the 1100 x22 tires we used standing erect and with his hands completely clear of the ring. At that time none of the class 1 common carriers that I knew of used any other type if wheel.

When I started there in the 60s we used to change our own tires on the road, every road tractor had a mounted spare tire standing vertically on the catwalk on the back of the cab and a 12 ton bottle jack and a lug wrench under the seat. Our trucks were all iron and so were the men.



I think you need to tell us what you are trying to do - passenger, truck, wheel barrow? And the type of equipment you are using.

But to answer your questions - yes, remove the valve core. That way the volume of air flowing through the valve is at its maximum.

If you want to know what the pressure to use for seating the beads - use the tank pressure to start - again, max air volume to get it to take air - but don’t allow the tire to exceed 40 psi. If the tire hasn’t seated by then you should find out what is wrong, then start over. People have been killed by exploding tires. Don’t be one of those!

And lastly, lube BOTH the tire and the rim. Not only does that make the tire easier to mount over the rim flange (without damage), but it allows the bead to seat more smoothly and evenly. Believe it or not, a tire not properly lubed can seat unevenly and develop high force variation - even to cause a vibration in an otherwise good tire and wheel.


On small tires I will use a ratchet strap around the tread of the tire and I always use a seating lubricant.
I too remove the schrader valve so I have no obstruction and get a good volume of air.

I leave the car and truck tires to the professional shop a few miles from my shop.


All good advise. Leave spilt rims to the professionals. Please.

A guy called the show, told about the time he got a tire repaired in rural Mexico. The llantero pitched in an ounce or so of gasoline then lit it. T&R recommended that we not try this at home.

Thanks, this post was motivated by a stubborn non-tube type wheel barrow tire that was giving me much grief. I was finally able to get the bead to set by applying a thin layer of rtv to the rim and tying a rope around the tire to compress it a bit. I set the compressor output to 60 psi to get it the initial seat, but the actual tire pressure never went above 20 pounds during the process. I discovered the setup I use with my compressor won’t work if the valve stem is removed for some reason. No air comes out. So I did it w/the valve stem installed.

Like I mentioned above, I’ve set the beads on both my Corolla’s 13 inch and Truck’s 15 inch tires before without nearly as much trouble. For the most part with those all I had to do was stand the tire vertical, and inflate to set the bead with 60 psi. Valve stem left installed. Sometimes I have to manually compress and roll the tire back and forth a little is all.

For those of you thinking of trying this yourself, remember I’m a diy’er and can’t speak to the safety issues. I presume it depends on the size of the tires and size of the rims. I always wear both eye protection and hearing protection when I do it. When the bead pops it makes a pretty loud bang. It really doesn’t make $$ - sense to do this job yourself; I’ve done it myself mostly b/c I was interested in seeing if such a thing is possible.

I bought a new wheelbarrow tube tire and rim to replace the old one after bending the rim to try and get the tire off. Got another wheelbarrow tire at the cabins that needs fixing, any hints? It was not that expensive, but save a few bucks if I can.

@Barkydog , do you mean you’ve a wheelbarrow tire to replace at your cabin, but aren’t sure how to get the tire off the rim without damaging the rim? The WB tire I was working on recently had been wheeled around while flat which distorted the sidewall, so it would have have fallen off the rim by itself I think. For auto tires getting the bead unset is the hardest problem. I’ve been using an 8 inch G clamp (and a home made foot gadget to spread the force) for that. Getting the tire off the rim after that involves using various pry bars and one really big screwdriver I have. For getting the first side off the rim, placing the tire face up on the ground (valve side toward you) seems to help, as that orientation places the valley inside the rim closest to the side you are removing. That valley inside the rim is what provides the extra space needed to remove the tire from the rim.

Never did real car tires, thought the wheelbarrow would be like a bicycle tire, one screwdriver and try and pull the bead over the rim, the rim bent first, tried 2 scredrivers, and both bent the rim, wondering if the rim was pressed on after the tube and tire were installed. Thanks!

I use some version of a curved pry bar to get the process started, as it helps lift the bead over the rim. A straight pry bar like a screwdriver shaft doesn’t do the job as easily.

One piece rims have a drop center to allow for skinning the tire off. If there is no drop center the wheel will separate somehow.

I have poured a generous dose of green goo flat repair into all the tires on my yard equipment and found it was worth the cost and effort. Even seeps at the bead can be sealed by removing the wheel pumping it up and flipping it until green shows up. I have a wheelbarrow that may be older than me with a dry rotted tire that keeps hanging in there with green specks showing up every time I use it.

And on that DIY effort to get the bead to seal I recall long ago seeing a shop place a bicycle tube of the appropriate size in the space between the tire and rim and inflate it to fill the space then adding pressure to the tire. The bicycle tube rolled out as the tire edge lifted up and made contact with the wheel.

I just ran across this and thought some might enjoy it.

that machine was STATE OF THE ART 60 years ago.