Mystery Flats
 

I had about 4300 miles on my stock wheels and a set of (never flattened) Gator Hardshell tires; the tires were rotated front to back at about 1800 but the rear was getting pretty worn, was looking for cord to appear at any time. I lucked into a set of upgrade wheels (the subject of another thread recently) and decided to change to the new wheels with new Gator Hardshells installed.

Last Thursday, Day 1 with new wheels and tires: I was 18 miles into a ride in a remote local area that we call the Blackwater. I was running down a couple of hundred foot hill at around 7% at speed and hit a wood bridge at the bottom, it was rough and the bike chattered hard going across. Three minutes later, the rear was flat, I assume a pinch flat. I had a spare tube in my underseat bag but had left my levers in my shop the day before. Only 2 miles of walking got me to an area with cell coverage so I could get someone to get me. I got home, pulled the tube and found the leak on the apparent underside of the tube. There is nothing detectable on the tire interior. Put in new tube.

Friday, Day 2: A whole 14 miles into the next ride near the house, another flat, nothing apparent. Pull tire, nothing on the inside, again the puncture was on the inside of the tube. Another new tube. Only had to walk a mile this time.

Saturday (today) Day 3: By this AM I was getting paranoid, we stopped several times for various reasons and each time I would feel the tire but it was inflated hard at each check. Near the end of the ride we decided to detour some to a public boardwalk by the bay. We stopped at the beginning of the boardwalk, I checked and the tire was good; 10 minutes later and we rode down the couple of hundred foot boardwalk and my tire was flat at the end. Just DAMN!!! By this stage, no way was I going to sacrifice another tube until I got a handle on what was going on but a 3/4 mile walk got me to the cars parked near the LBS. I pulled the tire in the parking lot and noticed that the rim tape was bunched. Took the whole mess into the shop where it was determined that the puncture was, again, on the inside of the tube. The LBS owner, who was a team mechanic, pronounced that the thin, non-adhered and loose rim tape is the culprit.

I now have a new tube and new rim tape (front and rear) and certainly hope that this is over.

Early last year a rash of flat tires led me to the Gator series of tires where I had over 8500 miles on two bikes without flats, until Thursday AM.

Sounds like you solved the mystery. I hope so! It's really annoying when you go through enough tubes to buy a new tire, thinking it can't possibly happen again. My front pinch-flatted this morning after hitting nothing more serious than a manhole cover with a 'lip' to the pavement. I had decided to try less pressure, as it was intended to be long slow distance, but apparently 100psi just doesn't cut it when your 195#. I normally have the front clincher at 110 and the rear at 120, and I'll be going back to that. Changed the tube and caught the group at the water stop.

Have not used any type of rimtape on single bike or tandem wheels in many years!
Nipple ends are recessed deeply in to rim (Velocity) and we use Veloplugs, small plastic plug that fills up each hole.
No bunching up, no shifting or splitting of rimtape.
Glad you found the cause!

I was going to suggest rim tape, but it looks like you've already covered that base. Good luck

Your mechanic is right, there is the cheap rubber rim tape and there is the better and much thicker plastic rim tape which is slightly stretchy and stretches over the rim, it stays in place better, there is also cloth tape that glues on. Not sure whether the plastic or cloth is better, I have the plastic on two bikes, see how long it lasts....

I suggest you go to Church on Sunday.

cheap rubber rims tapes have always caused me a problem so When I bought a set of Mavic wheels with a plastic rim tape- I was dubious. OK-Quality wheels with hopefully a quality Plastic tape and it was- or at least was good enough.

I have always used the "Velo" cloth tape on my wheels and it is adhesive and thick. No risk of a spoke or burr getting anywhere near the tube but there is a problem. They are thick and fill up the well of the rim. That can cause problems in that mounting or demounting a tyre and you can't get the bead right down in the well of the tyre. This can make it a 3 lever job to remove a tyre or even have to resort to the steel levers I have at the bottom of the repair box just so they don't come to hand easily. Steel against a soft alloy rim can bend the rim very easily.

With 2 extra tubes.

Velo is what's on it now. Though I think I have it now, I'll still be nervous for a few hundred miles.

I'm currently using the Veloplugs on one of my bikes, no problems so far. A clean and simple solution.

No need to be nervous. Had the Velo tape for 15 years now and no Flats from the inside of the tube. This works. Just make certain you get the bead down inside the Wel of the rim on the opposite side to the levers when mounting and removing the tyre.

I don't have anything to add about the flats, have had some rim tape issues myself in the past. I do question your switching a more worn rear tire to the front to get the less worn tire on the rear. You may regret that practice at some point, it's good to have some tread on the front tire.

It was called a really bad idea by The Late Sheldon Brown, his reasoning is that a blowout on a worn rear tire, while it often has a high PITA factor, it rarely causes a serious crash. A blowout on the front, will cause a loss of control as the front wheel stops turning, and that can be fatal at speed. Better to retire that worn rear tire, put a fresh one on the front and the old front on the rear.

Maybe "worn" is a relative term. I didn't mean worn out but more like 40% worn. Apparently I'm real bad on rear tires, I'll run them way down while there is no detectable wear on the front.

I still wouldn't put a worn tire on the front.... I expect the Raleigh will need a new rear tire by spring, after trainer season, so I will put the front on the back and buy a new front tire....

+1 on the rim tape. Took me way too long to learn that one. "Fool me once...." I'm not going any further with that.

Heard a lot of good things about velo plugs. Everyone I've spoken to that uses them loves 'em. Next time i need to replace rim tape....

FYI - I carry a small cotton ball in my seat bag. Use it to "wipe" the inside of the tire when I can't seem to find that cause of a tire side flat. It finds tiny glass shards and wires that might be difficult for the 50+ eyes to see.