7 flats in 7 weeks.

7 weeks ago I purchased a Motobecane Cafe Latte to replace a worn out Motobecane Elite FS. The Cafe Latte is a great bike except for the fact that I have now had 7 flats in 7 weeks since I bought the bike new. All on the rear. First thought it was the tires so I replaced the tires with a wider (31?) cyclocross tire after the second flat. Still had 2 more flats.Next thought it was a bad rim (Alex rim R500) so that was replaced, at no cost to me. Put liners in the tire, still having flats. Realized finally that they are pinch punctures on the side of the tube.so I took the liners out, still having flats. Recommended PSI is 35-70 and I check every time before I leave home using a digital gauge. I also check whenever I make a stop and get off the bike (coffee shop, bookstore, shopping, etc) using my ultra portable M1A1 highly calibrated thumb. I can feel it when the tire goes down and it happens mostly when I'm going around a corner. With myself and what I carry on the rack, figuring 70% of the weight is on the rear wheel, that rear is carrying no more than 200 lbs. Help! [IMG]/img/vbsmilies/smilies/hissyfit.gif[/IMG] What the hey is going on. I'm averaging 1 flat a week. My Elite FS had 3 flats in 4 years. This has gotten to the point that I can't rely on the bike. Frustrating not only for me but the guys at the bike shop as well.