Bicycle Mechanics - Tire Trouble

Hey here is a problem I am having, does anyone have advise?

Recently I had a flat on my rear wheel, when the flat was fixed there was a
pronounced low spot which made it imposible to ride on. the LBS says that
the bead on the tire was not correctly seated in the rim. I have been riding
and fixing my own flats for many years without ever seeing this issue. The LBS took a minute and made it right . Now here I am again with another flat and I have the same issue with the flat spot again. I have tried pushing on the tire and working it to hopefully allow the tire to expand out to the rim properly, without success.
Is there a trick to this proceedure which I am clueless about -- or--- is this a
sign of faulty material which no one wants to fess up about?

Please help me to understand?

Thanks

I have difficulty getting the bead to seat correctly on an older mtn bike rim. What I do is partially inflate the tire and bounce it on the floor, repeat with a bit more air, repeat again until its inflated. I can't go straight to full pressure or it wont seat correctly.

Some combinations are a PITA.
Also make sure the tire bead isn't "dragging" the rim strip along with it as it slides over.
A bit of liquid dish soap can help.

I recenlty bought a Kenda Thorn Resistant tube, and the installation instructions added an extra step:

Install tire on rim, make sure bead is seated evenly all around.

Inflate to 10 psi, check bead is eated in rim evenly,

DEFLATE and check bead again

Inflate (second time) to ten (10) psi,

check bead seat all around

then inflate to proper pressure.


The reason given is that the tube has a chance to settle in to it's correct position.

Some combinations are a PITA.
Also make sure the tire bead isn't "dragging" the rim strip along with it as it slides over.
A bit of liquid dish soap can help.

I agree with Bill, some combinations are horrid. Also, make sure the tube isn't interfering with the bead/rim interface

Instead of dish soap, I bought a tub of Tioga bead wax, which lubricates the bead/rim interface. A $5 tub will last years.

Also, if the problem is around the valve stem, you might have to push the valve stem into the tire and pull it back into position after you mount the tire, but prior to inflation. The reinforced area on the tube around the valve stem get between the tube and rim.

Thanks
I will try your suggestions

This happens fairly frequently. Many times a tire bead will need help seating to the rim consistently all the way around the tire.

After you install the tire, inflate enough such that the bead presses firmly against the rim, but such that the tire is still a bit soft. Look around the bead/rim interface and look for the "witness line" on the tire (a ring in the rubber just outside the bead area). The distance between the edge of the rim and the witness line should be consistent around the tire. If it's a problem combination, you'll need to work the tire out a bit in spots with your hands to expose the witness line.

When the distance between the edge of the rim and the witness line is the same all around, inflate to full pressure and check again. If it looks good, you're good to go. If not, deflate and start over.

One word. TALC. Powder the tube so it can't bind inside the tire (I wonder when this part of the procedure was lost to time) and get a bit of the talc on the bead, too. Follow the procedure outlined before, low pressure, work the bead to it's proper position, increase pressure. You may have to (gasp) overpressure a bit to make the bead slide out to "right" then drop back to proper service pressure. Get it set right soon or it will be more difficult to make the darn thing cooperate after it has been set off kilter for too long.

Talc on the tubes but Ruglide on the bead works for me.

Nick

One question: Does the "flat spot" line up with the valve stem. If so you just need to deflate the tire, push the valve stem in a little so the base of the stem is away from the bead of the tire. Then re-inflateallowing the tire to seat properly.

One question: Does the "flat spot" line up with the valve stem. If so you just need to deflate the tire, push the valve stem in a little so the base of the stem is away from the bead of the tire. Then re-inflateallowing the tire to seat properly.

Yes that was it entirely
I did not recognize that the tube had been pulled down and was holding the tire out just enough so that on the opposite side of the rim the tire would not seat in the rim it was pushed down a bit creating the flat spot. It's amazing how many times I tried to make this work, its also amazing that this is the first time this has ever happened to me ( I have done quite a few flat tires since commuting by bike from 1989)
Ah well its always good to discover some new wrinkle to this lovely bike culture. Thanks to all who contributed!!