I've been using tire liners like Mr Tuffy and Stop Flats for years. About 5 years ago I was talking to an employee at a LBS and he mentioned that they don't like using tire liners because they tend to wear a hole in the tube where the liner ends overlap. I never had a problem with this a thought it was complete BS until about two weeks ago when it actually happened to me. Clearly you can see the wear, on the tube, in the shape of the overlapping tire liner end. They, Mr Tuffy & Stop Flats, even have this problem listed on their FAQ's pages. (FAQ's pages which happen to be almost identical which leads me to believe that they are, in fact, the same company.) Quoted from their pages -
"Q I've read in some reviews that STOP Flats will wear a hole in my tube where it overlaps. Is that true?
A We've read that as well, and there is some
evidence that it's possible. In the early days, STOP Flats2 tire
liners were trimmed by hand. Once the volume of sales was measured in
millions rather than hundreds, we had a special precision cutting
machine developed that uniformly trims the liners to the exact size
and shape needed for maximum effectiveness. It is unlikely that the
overlap causes punctures using the current STOP Flats product. It is
possible that another brand of tire liner. especially the hard plastic
ones is the true culprits in many cases.
Dealers have told us that they grind or file down STOP Flats2's end
edges and they apply talc to the inside of the tire before
installation. This advice seems to make this particular problem
disappear. " -Exactly the same on the Mr Tuffy site. Just insert Mr Tuffy wherever you see STOP Flats.
Personally I believe this is a problem with lower pressure tires, like the one's I'm running now. I never had this problem with the higher pressure/lower volume tires I used to run. Is the lower pressure allowing the tire, liner and tube to flex more causing the rubbing/wearing on the tube? I don't know for sure but my personal belief is yes.