Question: Recently I punctured. After I replaced the tube and pumped up the tire, I hadn’t gone 300 yards before the same tire flatted again. I was out of tubes so had to hitch a ride home. What’s going on? — Benny S.
Coach Fred Matheny Replies: First, stop by your local bike shop and buy a tube repair kit. And ask how to use it if you’re not experienced. Keep it in your seat bag and you won’t be stranded again if you run out of tubes.
Whenever you flat, find out why. Don’t simply take out the punctured tube and stick in a new one. If a thorn or piece of glass caused the original flat, the sharp point is likely to be embedded in the tire casing. As you discovered, you’ll pump up the new tube and start down the road, only to hear that dreaded psssst.
During the repair, take the tire off the rim and gingerly feel inside the casing all the way around. Keep track by starting and ending at the tire label. Don’t rub your fingers too hard and get nicked. Some riders prefer to use a rag, which will snag on a sharp point, but fingers are less likely to miss it.
When you find the culprit, dig it out of the casing with your fingernail or a screwdriver tip from your multitool. Be sure to get it all.