Repairing and Preventing Flat Tires
How to Replace a Tire
- Take the wheel off the bike – Release your brakes, then the wheel.
- Remove the tube – Deflate the tube completely and remove it by pressing on the bead (edge) of the tire or using a tire lever so you can access the tube.
- Find the cause of the flat – Inspect the wheel, tire, and tube for the location and causes of tears or punctures. Be sure to feel inside the tire and remove any objects, as these could puncture your new or repaired tube immediately.
- Patch or replace the tube – When our riding, you may prefer to replace the tube with a new one and fix the damaged one later.
- Reinstall wheel – Be sure to reconnect your brakes prior to taking the bike for a test ride!
Preventing Flat Tires
Your first strategy should always be to make sure you are riding with the proper tire pressure.
Each tire has a preferred air-pressure range. Look on the tire sidewall for the recommended pressure. The following are typical pressures you may find on your tires:
- Road bike tires should run between 100 and 140 psi.
- Mountain bike tires should run between 30 and 50 psi.
- Urban and casual bike tire should run between 60 and 80 psi.
Under-inflation can lead to problems with “pinch flats.” This can occur when you hit a bump and your under-inflated tube compresses all the way to the rim, causing 2 small holes that resemble a snake bite. Over-inflation, on the other hand, doesn’t cause flats although it is possible to blow out a tube when excessive pressure is applied.
Use a tire pump or gauge to check your pressure. Higher-end tire pumps will include a psi gauge, but if you have a lower-end pump, you’ll need to carry your own tire pressure gauge. Be sure to know whether you have a Presta or Schrader valve stem (the slimmer Presta valve needs to have the top nut unscrewed before checking pressure).
Basic Tire Care
Inspecting Your Tread
It’s a good idea to periodically inspect your bike tires for embedded glass, rock shards or other sharp objects, especially after riding a route that has substantial debris. These small embedded items may not cause an immediate flat but can slowly work their way through a tire to eventually cause a puncture. Use your fingernail or a small tool to remove this debris before it causes a problem.
Tube Sealants
This option is handy because you can repair an existing flat tire with it or use it as a preventive measure to avoid future flats. The concept is simple: Squeeze in a bit of sealant through the valve stem to coat the inside of the tube. In the case of a small puncture or cut, the sealant quickly fills the leak and creates a plug that often outlasts the tube or the tire around it. Some downsides of sealants are that they can be messy to install, and sealants alone do not protect against large gashes or cuts.
Some tubes come with sealant already inside to offer a preventive approach to flat tires. These tubes are typically a thicker thorn-resistant variety, that when pre-injected with Slime, offer an excellent flat-avoidance strategy. These tubes may be a little more expensive, but can save you some time and a headache if you are riding in locations with lots of debris.
Inspecting Your Sidewalls
Periodically check your tire sidewalls and tread for excessive wear, damage, dryness or cracking. Tires with any of these symptoms increase your risk for a flat tire. If unsure about their condition, ask at your local bike shop to evaluate your tires.
Tire Liners
A tire liner is a thin strip of plastic that fits between the tire and the tube. This extra layer greatly reduces the chance of flats from thorns, glass or other sharp objects. Liners are popular and work well, but they do add more to the weight of your tires which adds noticeably to your rolling resistance in higher performance tires. If you ride in an area with lots of thorns or road debris, liners could be worth the weight.
