How to Check and Inflate a Child’s Bike Tires Before a Ride

To check and inflate a child's bike tires, start by finding the recommended pressure for the tire itself. The child's age doesn't set it, and neither does the maximum PSI printed on the tire. Next, look over both tires and valves for damage, use a pump head that fits the valve, and add air while you watch the gauge.

If the tire only lists a maximum, or the marking can't be read, don't guess. Look up the exact bike or tire specs, or ask a bike shop. Then recheck both tires before your child heads out.

How to Check and Inflate a Child's Bike Tires Before a Ride

Getting kids bike tire inflation right takes about three checks: the pressure target, the tire and valve condition, and the actual pumping. Do them in that order so you never add air to a tire that shouldn't be ridden anyway.

Find the Correct Pressure Before You Inflate

The right number comes from the tire, not from the rider. REI's tire-care guide says every tire has its own preferred range, and it tells riders to use the recommended pressure on the tire sidewall and check it with a pump gauge or a separate tire gauge. On a kids' bike, look for a line in PSI along the side of the tire. Then compare it with the bike maker's specs for the tire that is actually installed.

Look closely at what the marking says. A recommended range, such as a low and a high PSI, gives you a target zone. A line that only gives a maximum tells you the limit you must not go past. It does not tell you where to aim. If that's all you can find, or the print has worn away, look up the tire model or the bike's specs, or ask a bike shop.

General pressure ranges for adult road, mountain, or city bikes don't transfer to a child's tire. Leave them out of this decision.

Inspect Both Tires and Valves

Check both wheels before you pump. A problem found here can mean the bike stays home. Spin each wheel slowly and look at:

• Tread and sidewalls: Look for embedded glass, rock chips, thorns, worn spots, dryness, or cracks. REI's tire tread and sidewall inspection advice says these signs raise the risk of a flat. Pick out small debris with a fingernail or small tool.
• Rips, holes, or damaged casing: Park Tool shows how to check for visible tire damage and says a tire with a damaged casing should be replaced. Don't ride on it.
• Valve stem: Look for a bent or damaged stem and listen for hissing. On a Schrader valve, a loose core can cause a slow leak. A loose or leaking valve means no ride until it's fixed.
• Anything you're unsure about: Have a bike shop look at the tire before your child rides.

Inflate With a Pump That Matches the Valve

Bikes use three valve types: Schrader, Presta, and Woods (also called Dunlop). Your pump head has to fit the one on the bike. Schrader valves are the same style found on car tires. Presta valves are slimmer and have a small locknut at the tip.

1. Identify the valve and remove the dust cap if it has one.
2. Open a Presta valve by unthreading its small locknut. Park Tool's guide to Presta valve preparation explains that air can't get in until you do this. Schrader valves need no prep.
3. Fit the pump head firmly onto the valve and lock it if your pump has a lever. If you hear hissing while you pump, reseat the head.
4. Pump while watching the gauge. Stop once you're inside the recommended range, and stay below the maximum.
5. Remove the head, close the Presta locknut, and replace the cap.
6. Recheck both tires. Your child can ride if the pressure is in range, the tires hold air, and you found no damage or valve problems.

If you're choosing a portable bike pump, make sure its head fits the valve on your child's bike and that it has a readable gauge. Our mini bike pump comparison lists specs side by side.

FAQs

What happens if a kid's bike tire is underinflated?

REI says underinflation can cause pinch flats. These happen when the tire compresses all the way to the rim over a bump, which leaves two small holes in the tube that look like a snake bite.

Can overinflating a bike tire cause problems?

REI notes that overinflation doesn't cause flats in the usual way, but in extreme cases it can blow out the tube. That's one reason to stop inside the recommended range instead of pumping toward the maximum.

Do I need a separate tire gauge?

You need one only if your pump doesn't have a PSI gauge. REI points out that higher-end pumps usually include one, while basic pumps often don't. In that case, keep a separate tire pressure gauge with your pump.

How do I tell a Presta valve from a Schrader valve?

Park Tool describes Presta stems as about 6 mm (1/4 inch) across, with a small locknut on top. Schrader stems are about 8 mm (5/16 inch) across and have a spring plunger inside, like a car tire valve.