Cycling is an epic sport, and very little beats a decent day out on the bikes with your friends. When it comes to bikes, they can get complicated, they come in many different shapes and sizes, and they all have different parts. At Bike Test Reviews, we get asked a lot of questions about bike parts and love to answer them for our readers.
A question we have been asked recently is if all Presta valve cores are all the same. In this article, we want to answer that question by telling you what a Presta valve core is, why they are important to have on your bike, if they are universal and if it is worth carrying a spare.
What is a Presta valve?
Wheel manufacturers were making smaller rims to cater to skinny road bike tires and found the Schrader valve was too big and decided it was time to drop it smaller, and the Presta valve was created, which is 2mm smaller.
You will find a Presta valve on an inner tube or as a stand-alone valve for a tubeless system. They are what is used to regulate the amount of air in a space.
They were introduced on road bikes to start, but now you will see them on all kinds of bikes, such as gravel, mountain, and even hybrid bikes.
Are Presta valves better than Schrader valves?
A Presta valve is very different from a Schrader valve. Presta valves are much smaller and have a removable core compared to a Schrader valve. What makes Presta valves better is that they can be broken down and the core replaced in case of issues.
You will also find that Presta valves come in many different sizes, so they can be used on wheels with larger aerodynamic profiles and smaller valve holes.
How does a Presta valve work?
A Presta valve is a small two-piece valve. It has an external housing and an inner core. A Presta valve works in two ways.
To insert air, you unscrew the top of the core, put a pump on the top, and push the air inside using the pump handle. To remove the air, you unscrew the top and then push the screw down to release the air.
How do I remove the Presta valve core?
To remove a Presta valve core, you will need a special tool called a valve core remover. You will place this on the square point on the top of the valve below the screw and turn it anti-clockwise to unscrew it. They can be installed by reversing these steps and turning the screw clockwise.
Are Presta valves core universal?
Although you might find some Presta valves look different and come in different shapes and sizes, they all share the same valve cores. This means you are able to swap the cores out of your valves and replace them with cores from other valves.
What might you need to replace a Presta valve core?
There are many reasons why you might need to change the valve core after cycling hundreds of thousands of miles.
Here’s the reason why we have found we needed spare valve cores.
In case the screw breaks
If you get a puncture and replace the inner tube, you will find yourself having to pump some air in to seat the tire. On many modern pumps, you screw the pump onto the valve. If not used correctly, many of these pumps end up bending the valve core screw.
Once bent, the valve core screw is very difficult to bend back and will probably break. It’s better to just straight replace it.
Gets clogged up
This will be something you will typically see on a tubeless setup. It’s quite common if the valve isn’t fully tightened up or takes some sealant in from the inside of the tire for them to get clogged up. Instead of cleaning the old valve, it’s better just to replace it entirely.
If the valve is leaking
If your tire is losing air and you can’t find any puncture holes, then you might be losing it at the valve. Sometimes the seal on the valve can become worn and slowly leak air over time. Instead of replacing a seal, just replace the valve altogether.
Valve cores are typically all universal. We highly recommend taking some spare cores out when you ride in case the screw top breaks or gets clogged with sealant. They cost next to nothing and weigh absolutely nothing.
Robbie Ferri has spent years working in a bike shop, has worked with industry leading brands on product creation, has been a semi pro athlete, and is a fully qualified strength and conditioning coach. He has broken World Records, bikepacked all over the World and raced ultra distance at a top-level.