Bicycle Mechanics - Flat spots on Conti tires

I am running Continental Contacts 26 x 1.75 (the 900 gram flat resistant ones) and both have single flat "spots". What is up? I have deflated and remounted several times to no avail. I have also tried pressures from 30 - 80 psi, and the flat spot remains. I normally run about 45 psi because these tires are so unforgiving at higher pressure.

Oh yeah, and my wheels are true and not the cause of the flat spots.

Are these tires just crap, or am I unable to mount a tire? I've never had this problem with any other tires. The unbalancedness is definitely noticeable when riding.

I would search the forum, but the function is not working for me...

Do you inflate with the bike resting on its tyres at all? I've found that doing this makes the tyre not sit evenly, particularly if going from empty (say after fixing a flat), and can result in a noticeable unevenness to the ride once it's inflated. For this reason (and also easier access) I always flip my bike upside down when pumping up tyres.

my suggestion is to deflate the tires and make sure that the tire isn't getting hung up on the rim strip. you can also spray some soapy water (simple green or windex also work) between the tire and the rim where you have the low spot and then pump the tire up.
assuming you have a floor pump or a friend willing to help, grab the low spot with your hand and squeeze it as you inflate the tire. this helps keep the tire off the inside of the rim so it has a chance to seat properly.

Is it an actual flatspot? (Rubber is worn away) Or just not seating correct in one place. One trick that usually always works is soapy water on the bead.

Then pump it up.

Is it an actual flatspot? (Rubber is worn away) Or just not seating correct in one place. One trick that usually always works is soapy water on the bead.

Then pump it up.
+1.

Pump them good and hard and they will "pop" into place. Don't be afraid to pump it past the limit on the tire. They are designed to hold at 1.5x the recommended pressure written on the tire.

If they aren't new and the flatspot is in the tread, any chance someone skidded them by locking the brakes and ground the flatspot that way?

Thanks for the input. It is not a worn tread related flat spot. I've tried to reseat the tire several times but will have someone squeeze it and use soapy water as I inflate.