So I posted yesterday about the Monster Cookie ride in Salem, OR. I had several flats that day - 4 on the ride and another by the time I got home - the tire was flat again. Only one was a "real" flat. The first one was clearly a puncture of the tire and tube. OK, I can live with that - fix and off I go.
The rest of the flats though were "mystery" flats that I could just not figure out. Flats at 20 miles, 40 miles, 55 miles, at the finish, and then at home. As I had my sunglasses on and I was out on a ride, I did not dive deep into the diagnosis, I just threw tubes at the thing and rode on. When I ran out of tubes by the third flat I patched and replaced...until I got home and the tire was flat yet again.
I decided to start with what I have changed - I recently (as in just a few days before the ride installed velopulgs on my two front trike wheels - the ones that flatted all day. I already had them on the back wheel for almost a year, and I have them on three other bikes that run velocity rims and on a spare set of velocity wheels for the F5 high racer.
I had noticed on the ride on all flats after the first one that the hole I found was on the inside of the tube - where the tube hits the wheel - as opposed to the tire. The first few times I figured in my changing I must have accidentally let a tiny rock get into the tire before I mounted it... but there never was one.