I've never had a need for the cotton ball/nylon treatment. In a couple cases maybe it was a bit of work to get the shard of glass out of the tire. I've also ridden (slowly and careful to avoid even the least crack or stone) clincher alloy wheels with flats and never had a problem, though certainly not ideal by any means. The other day I saw something on my front and stopped and realized there was an embedded thorn. I left it alone and made it home (maybe 15-20 miles?) without problem (avoided any sort of hard cornering). At home I removed it and immediately (well 2-3 minutes) the tire was flat. Then inspected the rear and also had a thorn, so I got to repair 2 tubes at once. I would say it's not unusual to have a "flat" which if you don't check your wheels after a ride you find out the next day when the tube has lost pressure over night. It does help to have a spare tube (not just kit) on the road as on these slow leaks it can be very hard to find the location if you remove the tube and don't keep track of where exactly on the tire the cause is/was. I've also had snake bites from time to time (not allways the most diligent about keeping proper pressure and not always the best maintained rim tape).

scott s.
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