The duct tape on the liner is bad. The directions specifically say to not tape the liner. It may be causing the liner to flex & "bounce" as the tire rolls, depending on the tire psi. I've run Mr. Tuffy's for 4 weeks now (350+ miles) without any problems, running in some basic Cheng-Shin $10 tires, and haven't had any thumping nor any flats since I've installed them. I was prompted by getting a flat on my first ride to work, and I haven't had another one since (knock on wood!). In summary, try untaping the liner and giving it a shot.