What Is a Pinch Flat? (And How to Avoid Them)

The first time I heard the word “pinch flat”, I didn’t know what it was. But as you may have guessed, a pinch flat is a certain kind of flat, but what exactly is a pinch flat?

A pinch flat, also called a pinch cut or snakebite, is a type of flat tire caused by the inner tube being pinched between the rim and tire. This can happen when hitting curbs, potholes, or flat edges hard enough that the tire bottoms out. Pinch flats are easily identified by two small holes in the tube 1/2″ apart.

What Causes Pinch Flats?

I remember my first pinch flat. I was in a local park and decided it would be cool to hop up some granite stairs. The next thing I knew, I was halfway up the stairs and my tire was flat.

Pinch flats happen when you hit sharp edges, like on a pothole, curb, and in my case, stairs. If you hit a sharp edge hard enough, your wheel will bottom out. The tire will pinch the inner tube between the rim. This often results in two small holes next to each other, which is why it’s called a snakebite. It looks like the bike made by a snake.

In some cases, if you hit an edge hard enough, you can even damage the rims, but the tire is usually not damaged.

How to Avoid Pinch Flats

The main cause of pinch flats is underinflated tires. Having more pressure in your tire will help prevent these kinds of flats. Getting in the habit of checking your tire pressure before each ride is recommended.

When you are checking your tire pressure, make sure you are using the same tire pressure gage each time. No two gauges are the same and will give slightly different readings. Any pressure gauge will do, but these pencil tire pressure gauges are cheap, small, and work great.

And of course, avoiding potholes is always a good idea. But if you are a heavy rider or are on bad roads that can’t be avoided, getting bigger tires and thicker/stronger tubes can help.

Going tubeless is also an option. Since there is no tube, it’s impossible to get a pinch flat.

Some people claim that coating the tube with talcum powder before installing it will help prevent flats. The idea is that the powder acts as a lubricant, allowing the tube to move freely without getting pinched. While some say it’s very effective, others call talcum powder a myth.

What About Pinch Flats on Mountain Bikes?

Avoiding pinch flats on mountain bikes is a little trickier. This is because mountain bike riders want their tires at lower pressure for better grip. And as we know, lower tire pressure means there’s a higher chance of getting pinch flats.

What some mountain bike riders do is lower their tire pressure then raise them back up until they don’t get flats anymore.