Picked up a couple like new CST 700c40 tires and replaced old cracked 700c45 tires. Reused the tubes. Used wheels have some runout but not bad. The smaller tires were difficult to mount tube seemed to big a diameter when I put them inside the new tires and excess length tube may have bunched up in a spot. After mounting both tires have a flat spot. The witness line they cast above the bead is sunken below the rim for maybe 6" and that's where the flat spot is. I have inflated and deflated them several times, worked my way around the bead by hand several times, dropped them sharply on the floor several times around the whole diameter trying to get the tire to seat correctly. This has always worked for me in the past. I'm thinking either the tires are made wrong or my tubes are too big to work with the smaller tires. I don't remember what the tubes I'm using are labeled for size. I notice they seem to cut off at 32mm for smaller size?