Several years ago I was enjoying a beautiful ride on a quiet country road. At the end of a long straight, I leaned the bike to turn right. Before I knew what had happened, I was on the ground. A quick scan revealed no broken bones, some road rash, and a flat front tire hanging off of the rim. The tire had a puncture and had slowly gone flat. I hadn’t noticed it. When I leaned for my turn, the tire rolled off sending me to the ground.
I don’t like flats. I don’t like getting them, and I don’t like fixing them. Fortunately, there are several options available to help prevent them.
The Nut That Holds The Handlebar. The most useful piece of preventative equipment is the rider. Scanning the road ahead for items that could cut or puncture a tire can make other preventative measures moot. On most roads, you will find a clean area that is swept free of debris by passing cars and trucks. Outside of this area, you will often see pebbles, bits of rubber, and other junk. While this area often appears to be free of things that could cause a flat, there are often bits of wire, glass, and other nasties hiding there. It’s often tempting (and sometimes necessary) to ride here because it is further from passing traffic, but a higher incidence of flats is likely.
Thorn-Resistant Tubes. Thorn-resistant tubes are just like regular inner tubes except that the rubber on the outer portion is thicker than normal. This makes it a bit harder for an object to penetrate and cause a loss of air. In wet weather, however, water will act as a lubricant making it much easier for a sharp object to penetrate the rubber.
Tube Sealant. The best thing for thorns is a self-sealing tube. I use Specialized Airlocks, but others have used Slime with similar success. The sealant inside the tube will seal most punctures but will do nothing for cuts. When the tube is cut, the hole is too large to be filled with sealant. Sealant can be added to Schrader valve tubes relatively easily. Presta valve tubes generally must be purchased with the sealant already installed.
Tires With Aramid Belts and Casing. Aramid (Kevlar is the trademarked name) belts and casings are good at stopping cuts, but not punctures. Aramid is a fabric, and a pointy object like a thorn can slip between the threads. Aramid plus sealant is a good combination. Don’t confuse a tire with an aramid belt or casing and a tire with an aramid bead. An aramid bead is used to decrease tire weight and to make the tire foldable. It offers no flat protection.
Specialized Armadillo Tires. Specialized’s Armadillo casing is unique. It is an aramid casing, but Specialized worked with Dupont to develop a method to seal the holes in the fabric weave. This means that Armadillo tires are very good protection against both flats and cuts. The only other product I am aware of that claimed to seal the holes in aramid fabric was the Spin Skins tire liner. Unfortunately, the friction between tube and tire caused these liners to break down very quickly. Riders would get a flat, remove the tire, and discover many tiny pieces of tire liner inside.
Tire Liners. Most tire liners, like Mr. Tuffy, are not made with aramid. They are made of a variety of different materials, and they act much like a thorn-resistant tube. The more material needed to be penetrated by a sharp object, the greater the flat protection will be. One word of caution, however. I have seen a number of flats caused by the liner itself. The edge of the liner, if not properly tapered will eventually cut into a tube. I have also seen other liners that have broken down through use like the Spin Skins.
For the best flat protection, I typically recommend either Armadillo tires or an aramid-belted tire combined with a tube filled with sealant.