Nobody takes me seriously around here anyway, so use the following at your will. But DON"T come back with some lamea$$ completely unwarranted and unbidden crap like "prove it!".. or "that doesn't really make sense, and (tho i haven't actually tried it yet) here's why it doesn't..", or "yeah, I had one of those wire flikkin' thingamabobs on my tires when I was 10 and it didn't do a thing". Try it or don't. Noone cares but you.
The following will save you from about 50 percent of your flats. Or about half of them, or somewhere close to half the way between most and almost, or darn near in the middle of ultimate success and catastrophic failure... depending upon how carefully you install it.
Create a "mud flap" out of innertube rubber, no wider than the tire, and affix it to your bicycle such that it is very lightly resting on the tire. If you have rim brakes, the brake mounting post is a good place to put this. Cut an arc out of the rubber so that it somewhat conforms to the tire's radius when resting (gently) against the tire. Accuracy is not too important since soon enough the tire will wear the flap to a perfect fit.
Because the innertube rubber is so pliant, it does not put enough pressure on the tire to put drag on your forward progress or wear the 'flap' so much that it's no longer touching the rubber of the tire. It wears to a point of equilibrium such that it's just very gently brushing the surface of the tire of debris while you ride and makes no noise. Many (50 percent?) of the items that cause flats begin by just barely embedding themselves in the rubber, and on the first go-around they're barely hanging on. Each time your tire meets the road, that little thorn or tack or nail gets pushed just a little farther in. Eventually, It gets worked all the way in to the tube, and there you go. You're walking.
By gently brushing the tire each revolution, you brush away many (obviously not all) of the loosely attached menaces before they get a chance to keep getting pushed in further. I've been touring and racing bicycles since I was 13. I've got a godzillion miles on sew-up tires (that's how old I am now). Flat sew-ups were a NIGHTMARE. I've gotten lazy since I don't use the sew-ups any longer, and don't insist on having the innertube flap installed on all my bikes. It's so easy to fix clinchers, and I don't put thousands of miles a year on bikes anymore, that I'm less adamant about avoiding flats. But this isn't voodoo, and I'm not selling anything. Just assuring anyone who's curious that it works. Use it or don't. I don't want to hear about it.
