Riding a bike with low tire pressure can ruin the tire and make it hard on the rider. Tires with Schrader valves are easy to inflate. Here we look at the Schrader valve, what it is, the advantages of using a Schrader valve, how to replace the valve core, and how to pump up a bike tire with a Schrader valve.
What’s a Schrader Valve?
You have probably seen a Schrader valve a million times and didn’t know that’s what it was. Schrader valves are on rimmed bicycle tires, motorcycle tires, and all car tires. People often refer to them as car valves or American valves.
When comparing a Schrader valve to a Presta valve, the Schrader valve is shorter and wider. Unlike the Presta valve, there is no locknut to be opened before inflating or deflating the tire.
Looking inside a Schrader valve, you can see the hollow nickel-plated brass tube with threads on its outside. Inside the tube’s center is a metal pin that runs the tube length to the end of the valve. The valve’s core has a spring and poppet valve, which is removable and easily replaced.
The cap on the top of the valve is threaded and made of metal or plastic with an o-ring or rubber washer that keeps the cap in place as the tire vibrates. When a Schrader valve has a faulty core, the cap’s o-ring helps to keep the air in the tire. The cap’s true purpose is to keep out dust and mud, though some people think it keeps the air in the tire, which is partially true. Schrader valves are the same size, so all tools and pumps are universal.
Changing the Core in a Schrader Valve
Replacing the valve core sound much more complicated than it is! There is a core remover tool online and in bike stores, but a needle-nose plier will do the job too. The spring valve cor is about $2 for one and a dozen for about $7. There are even kits that come in a box with an assortment of Shrader valves and core springs, plus the tool that is less than $20.
- Needle-nose pliers
- Replacement valve core
Step 1: Remove the valve stem cap and set it aside.
Step 2: Using the needle-nose pliers, grip the top of the valve core and screw it counter-clockwise until it comes out of the valve.
Step 3: Once the old valve core is out, Use the needle-nose pliers to screw in the new valve core clockwise until you can no longer screw it down.
Schrader valve advantages
- More durable, do not bed as easy as a Presta valve
- Prone to less damage because it is seated in the center of the valve stem
- Cores are removable using a unique tool or pliers on bikes and cars
- The spring-loaded check valve makes them easy to use
- Pumps for Schrader valves are universal and available in every gas station and repair shop.
Check the pressure first
Before inflating the tire, you need to know the PSI for the tire. Check the bike manual or the tire’s side for your specific PSI. The first PSI number is the lowest pressure for that tire. The second number is the highest tire pressure. If you are a bit heavy or are carrying equipment, you will need to adjust the tire pressure to the higher end. Remember that extreme heat will expand the tire while colder weather will constrict the tire. The tire pressure will need to be adjusted accordingly.
The following are the recommended PSIs for bike tires:
Mountain bike tires – 25 – 35 psi
Hybrid/cruise cycles – 40 – 70 psi
Road bikes – 80 – 130 psi
Before inflating any tire, check the tire pressure with a tire gauge. If the PSI falls between the recommended numbers, there is no need to inflate/deflate the tires.
Pumping up a Tire With a Schrader Valve and Foot Bike Pump
Most bicycle floor pumps have a nozzle for a Presta and Schrader valve. The larger is for the Schrader valve.
Step 1: Using the Schrader nozzle, place it firmly on the Schrader valve. Ignore the hissing. It is a bit of air leaking out!
Step 2: If the pump has a lever, you need to pull up on the lever and turn it 90 degrees.
Step 3: Place your feet on each side of the pump (there is usually a base where you can place your feet.) Using both hands, pump the handle up and down until you get the needed PSI.
Step 4: Once you have the desired inflation, lower the lever and rotate it 90 degrees to the starting position. Quickly pull the nozzle off to minimize air loss.
Step 5: Put the valve cap on and screw it down. Time to ride!
Pumping up a Tire With a Schrader Valve and Hand Bike Pump
Many people find using a hand pump more difficult than a foot pump due to the lack of consistency in the pumping, and you need to pump more to get the proper pressure.
Step 1: Remove the valve cap and set it aside for later.
Step 2: Choose the Schrader nozzle and place it on the valve by pressing down or screwing it in place.
Step 3: If your pump has a low volume/high volume option, choose the higher volume. Pump until it gets more difficult to pump, then switch to the lower volume choice.
Step 4: If the pump has a pressure gauge, monitor the pressure as you pump until you are at the needed pressure. For a pump without a gauge, pump until the tire is firm to the squeeze. Once you remove the nozzle, you can recheck the tire’s pressure.
Step 5: Pull or unscrew the nozzle and screw on the valve cover once you reach the needed PSI. Now you’re ready to get pedaling!
If you should need to let, some air out of an overinflated tire, press on the valve core to let out bursts of air until you achieve the desired pressure.