QUESTION: It seems like I’m constantly getting flats on my road bike. I’m pretty good about avoiding glass and potholes, and I have decent tires and tubes. I’ve even had the bike shop check my wheels to make sure there’s nothing wrong. How can I fix this problem? —Leroy S.
RBR’S STAN PURDUM REPLIES: Often this problem of frequent and repeated flats is the result of a foreign object getting embedded in the tire. I once had a good quality tire that has a reputation for not flatting easily, go flat while on ride. Working at the side of the road, I pulled out the tube and by reinflating it, I checked until I found a small puncture. Then, feeling with my fingers, I worked my way around the inside of the tire searching for anything irregular that might have caused the hole. When I found nothing, I figured the offending object must have penetrated the tire and tube and then been expelled as the wheel continued to spin. So I remounted the tire, using my spare tube.
I completed the ride without further tire problems, but the next day, while riding in a different location, the same tire went flat again (and, of course, it was the tire on the back wheel, which always takes more effort to change). The tire had quite a few miles on it, and it happened that I was near a bike shop. So I walked my bike to the shop, and purchased a new tire and tube. The mechanic offered to mount the tire, so I let him. But I took the old tire home with me, and that evening, I examined it on the inside again, this time under a bright light. I essentially turned the casing inside out, section by section, and I eventually spotted a tiny stone ensconced in the rubber. Running my finger over the stone I didn’t feel much, but there was a slight sharpness to it, and I imagined that when an inflated tube pushed against it, revolution after revolution, that sharpness was enough to eventually poke through the tube.
I was on a multi-day group ride once where one rider was averaging two flats a day. He was riding with a friend, and soon he had used both of his spare tubes, both of the friend’s spares, and was reduced to borrowing tubes from other riders. Finally, an experienced rider volunteered to examine his tire. He removed it from the bike and carefully checked the inside until he finally found a tiny shard of glass, which he removed with tweezers from his own tool kit. They remounted the tire, and the rider completed the trip with no further tire problems.
Other objects sometimes found in bike tires include tiny wires cast off from truck tires, thorns, nails, screws and miscellaneous scrap. And even if you are, as you say, good at avoiding potholes and glass, you can’t see and dodge every mini piece of road debris.
By the way, if you don’t want to risk getting a bloody finger while feeling around in your tire for embedded objects, carry a cotton ball in your kit for that purpose. It will snag on anything sharp. (Thanks to RBR reader Steve Shepherd for this tip.)
Another common cause of flats is when the end of a spoke pushes down into the tube. A giveaway of this is when you are examining the tube and find the hole on the side of the tube that faces the rim. Sometimes you’ll find two holes, where the spoke has punched clear through the tube, leaving a hole on both the rim side of the tube and tire side of it. To avoid this problem, 1) make sure you have sturdy rim tape in the rim and 2) keep your tires inflated to the recommended level so that they don’t bottom out on the edge of a pothole or when going over a curb.
Unless you are racing, it’s worth buying tires that are made for durability rather than speed. Some are even advertised as nearly puncture proof because they have a thick layer of tough material between the tread and casing of the tire. I generally find those to feel “heavy” and sluggish when riding, so I generally choose puncture-resistant tires, like the Continental Gatorskin. Even they may flat occasionally, but they put more material between the road and the tube than the tires designed for maximum speed.
The other option, of course, is to switch to tubeless tires, which run with a liquid sealant in the air pocket between the tire and the rim. The sealant will plug small punctures while rolling.
But back to tires with tubes, here’s a practice that you may find useful whether you have frequent or only occasional flats: When you mount your tire, position the tube stem so it aligns with the center of the brand logo on the sidewall of the tire. You may have noticed that new bikes usually come from the shop with the stem aligned with the tire logo. It’s a practice used to make things look tidy on the bike, but it also helps with finding foreign objects in the tire. If you do have a puncture, when you remove the tube and find the hole, you can lay the tube back on the tire and know about where the offending object penetrated the tire. That’s where to check for an embedded object, if there is one.
Stan Purdum has ridden several long-distance bike trips, including an across-America ride recounted in his book Roll Around Heaven All Day, and a trek on U.S. 62, from Niagara Falls, New York, to El Paso, Texas, the subject of his book Playing in Traffic. Stan, a freelance writer and editor, lives in Ohio. See more at www.StanPurdum.com.