There are few things more frustrating than having a triathlon season marred by flat tires. Sometimes it seems like bad luck, and if it happens again, it's like bad luck that won't go away. Early in my triathlon career, I had a summer where it seemed like I could not stop getting flat tires. The upside was that I improved greatly at changing the tubes. The downside was a number of ruined training rides, and a race in which I had two flats in the same race.Looking back on it, I'm certain it was a single thing that caused all of those flats. The first one may not have been preventable, but all of the ones after that could have been. Read on for how to avoid this repetitive misfortune.
The most frequent reasons for flat tires are:
The first one is unlikely to happen unless you have not yet adopted the triathlete's obsessive habit of inflating to 120PSI before each ride. (Give or take, depending on your weight and the road conditions.) If you don't inflate your tires before each ride, or you don't have a floor pump, your tires will become low and when you take a corner or hit a pothole, the tube can move around and end up caught between the rim and the outside of the tire, resulting in the a predictable flat. Imagine taking a barely inflated balloon and smooshing it hard between a metal pen and a hard rubber mat. You might have a slow leak at first, but eventually all of the air will go out.And triathlon training is expensive, so you might think you don't really need a floor pump. However, the electric pumps used for car tires are not made for the high pressure of road bike tires. Car tires usually have a maximum pressure of 30 or 35 PSI. Bike tires need 110 or 120 PSI. I once burned up an electric air compressor that came with my emergency roadside kit, trying to fill my bike tires with it. Hand pumps will also never achieve the pressure you need. A good manual f floor pump is essential. And it costs less than the number of flats you will endure without one.
Punctured tubes are a major cause of flats. It's easy to run over a shard of broken glass on the road or a bike trail. It seems impossible to avoid, and just a matter of luck, but there are steps you can take to diminish the number of times you suffer.First, if you run over a small shard of glass, it's unlikely to puncture the tube immediately. The hard rubber of your tires (the purple and dark purple in the diagram) is there in part to protect the delicate surface of the tube inside (the pink), which is more like a balloon. Often the sharp item you've picked up on the road won't penetrate through to the inside of the tire right away. If you wear bike gloves with leather palms, every time you finish a ride (or ride through a pile of glass) stop and spin your tires gently while running your gloved palm over them. This will often knock miniscule bits of glass loose before they have time to embed in the tire and work their way through to the inside.Second, if you ride in areas with a lot of broken glass (kids throwing beer bottles in parks, or unswept roadside bike lanes) you may want to invest in heavier tires, or tires with goop inside that protects the tube.However, if you just happen to get that freak flat tire, and you have no idea what you even ran over, please remember this: the source of the problem is likely STILL IN YOUR TIRE. Whatever sharp thing caused the problem had to work its way through the tire, and therefore the majority of it is probably still stuck there, protruding through and poking it's nasty sharpness into your inner tube. It's likely you won't be able to see it. If it worked its way through, it's probably cloaked in rubber and dirt. So follow these steps to make sure you don't have a repeat:
Here's a great YouTube video I recommend from Trek. Then you need to practice at least once, if you've never done it before. Practice in your garage or basement, where you can sit comfortably, out of the weather, and take all the time you need. Remember as you are practicing that in real life, you'll be on the side of the road, dirty and sweaty, possibly in a patch of poison ivy, tired, and under some sort of time constraint.