Home › Articles › How to Fix a Flat Bike Tire in 8 Steps
How to Fix a Flat Bike Tire: The 8-Step Roadside Method
A flat tire is the difference between a 15-minute pause and a walk home, decided entirely by whether you've done this once before. Carry a spare tube, two tire levers, and a mini pump or CO2 inflator, and follow these eight steps. Practice once in your living room — the first attempt takes 30 fumbling minutes, the second takes 12.
The eight steps
- Remove the wheel. Shift to the smallest cog first (rear flats) so the wheel drops out cleanly. Open the quick release or thru-axle; for rim brakes, release the brake caliper. The rear wheel is not harder, just scarier — pull the derailleur back and the wheel falls out.
- Deflate fully and unseat the bead. Push the valve to empty the tube, then pinch the tire toward the rim center all the way around to loosen it.
- Lever one side off. Hook one lever under the bead opposite the valve, pry it over the rim edge, then run the second lever around. One side only — the tire stays half-on.
- Pull the tube, find the cause. This is the step people skip and regret. Pump a little air into the dead tube and locate the hole, then check the matching spot on the tire. Run fingers carefully along the tire's inside — glass, wire, and thorns that stay embedded will kill the new tube in a mile. Two holes side by side ("snakebite") mean a pinch flat from low pressure, not debris. Check the rim tape covers all spoke holes.
- Install the new tube. Inflate it just enough to hold shape, insert the valve through the rim, and tuck the tube fully into the tire.
- Reseat the bead by hand. Work the open bead back over the rim with your palms, finishing at the valve. Use thumbs and patience for the final tight section; levers here are how new tubes get pinched. Push the valve up into the tire briefly to make sure the tube isn't trapped under the bead.
- Check, then inflate. Spin the wheel and inspect both sides — the bead line should sit evenly, no tube peeking out. Inflate to your normal pressure (see maintenance basics for pressure guidance). CO2 users: one 16 g cartridge fills a road tire; note that CO2 leaks out overnight, so re-pump at home.
- Reinstall the wheel. Seat it fully into the dropouts, close the skewer or axle firmly, reconnect the rim brake, and spin to confirm nothing rubs. Give the brakes one hard squeeze before riding.
Prevention beats repair
Weekly pressure checks eliminate pinch flats; puncture-resistant tires (or tubeless setups with sealant, which self-heal small punctures) handle debris; and replacing worn tires before the casing shows ends most flat streaks. Riders who "get tons of flats" almost always ride soft, worn tires. Stock your kit from the gear guide and you'll pass the stranded riders instead of being one.
Keep exploring
Put these numbers to work with the free CalculateBike speed and calorie calculator, browse the cycling gear guide, or read more cycling articles. Prefer two feet to two wheels? Our sister tools CalculateSteps and CalculateRun cover walking and running.