Bicycle Mechanics - Tire out of round?

I had my bike up on the stand today and noticed the back tire appears out of round. The rim spun true, but there is a noticeable high spot on the tire as it spun.

There is no damage to the tire and it has less than 400 miles on it.

Could it be that the bead is not positioned correctly on the rim? Wondering if I should let the air out and re-seat the tire?

Thanks for any suggestions.

Sure sounds like the bead isn't seated correctly. Yes, you should let the air out, re-seat the tire, and pump it back up. Shouldn't be a big deal.

Originally posted by SteveE
Sure sounds like the bead isn't seated correctly. Yes, you should let the air out, re-seat the tire, and pump it back up. Shouldn't be a big deal.

Sounds like a pinch-flat waiting to happen, too. (The tube gets pinched between the bead and the rim, abrades, and *pop!*)

Remove one side of the tire and carefully inspect the tube before you reinstall it.

RichC

Thanks for the tips. I will take steps before my morning ride.

If you pump up to 70-80# or higher pressure, an unseated bead will let you know by blowing off the rim and destroying the tube.
Lower pressures may allow the tire to stay on. Wire bead tires are a little more tolerant of unseated beads than kevlar beaded tires. Another possibility is a bulge in the carcass of the tire. If the carcass is defective or has a multi strand tear or weak spot you can get a bulge in the tire. This is not very common but does occur. Steve

This is a 80# 700C tire, kevlar belted. I deflated the tire today and reseated as suggested by SteveE. Still had the high spots. The tire does not bulge, simply has high spots - two of them. I think I'll take it to a LBS and have them take a look.

Kevlar BELT is under the tread and is a protection against punctures. Kevlar BEAD versus wire bead: the tire with a kevlar bead can be folded up and sold in a small box. With a wire bead the tire cannot be folded and is sold looking like a tire, it is fairly rigid by comparison (and harder to mount on the rim). Steve

Thanks, for the info Steve. I'm takign the tire off the bike tomorrow and running it to my LBS for a solution. I'll be starting a regular commute soon, so want to make sure I've got a solid tire to start with.

I took the wheel off today and visited my local LBS mechanic. I trust this fellow's opinion - been in the business for about 20 years.

He put the wheel on a wheel stand thingy, spin it around a few times and tested the rim. Rim was fine.

Next, he pulled out his "tire pliers" and yanked on the tire for awhile (trying to seat the tire better into the rim.)

Nothing changed.

He said he's seen this a lot and doesn't feel it's a saety concern. Some rim and tire combos just don't "fit" as well as others.

I think I'll ride with this tire for a couple hundred more miles and have it checked again. Then make a decision on possibly replacing it.

Thanks to everyone who commented. Much appreciated.