How to Fix a Flat (Step by Step Instructions)

Fix-A-Flat Supplies:

• Bicycle pump or Co2 Cartridge and Co2 inflator
• Patch kit
• Spare tube or 2
• 2 Tire levers

FIRST: Understand the Terms.

The Tire is the round rubber circle that actually makes contact with the road.
The Wheel is the metal frame that the tire sits on.
The Rim is the side of the wheel, where the tire lip rests. (The part that the brakes grab on to.)
The Tube is the rubber thing that’s filled with air. So you see, you don’t really have a flat tire, you have a flat tube.


1. BREATHE. Then remind yourself that you CAN do this!

2. REMOVING THE WHEEL. First release the brake on the wheel that has the flat (the mechanism is usually found right above the wheel), then remove the wheel from the bicycle. IF REAR wheel – Shift to put your bike into the smallest cog on the back and front cassette before removing the wheel. (This releases the chain and makes it easier to reinstall at the end.)

3. REMOVING THE TUBE. Empty the remaining air from the tube. Then use tire levers, insert them between the metal rim and the rubber tire bead (the curved edge that hugs the metal rim) on either side. Push both tire levers away from the wheel and remove one side of the tire bead. You need to remove only one side to change the tube. Remove the valve cap (where you pump air into the tire), then pull the tube from inside the tire.

4. INSPECT THE TIRE. Carefully inspect both the tire and the tube for the cause of the flat by running a cloth or tire lever inside the tire. Any sharp objects will snag the fabric. Remove the debris. Visually check the tire tread for other culprits or large cuts. Also make sure that no spokes or rough edges are rubbing along the inside of the metal rim. (If tire is blown out or severely damaged you will need to replace the tire or if on the road, use a folded dollar bill or gel wrapper to cover damage inside the tire until you can get to a bike shop.)

5. INSPECT THE TUBE. Pump up the old tube, then check for a leak. Choose to either repair the old tube using a bike patch kit (use the instructions on the repair kit you have) or replace it with a new tube.

6. INSTALL NEW/FIXED TUBE. Take your patched or new tube and insert it back into the tire. First install the valve in the valve opening, then work the rest of the tube into the tire all the way around. Pull the rubber bead of the tire back toward the metal rim. The tire bead should drop down into the metal rim. The bead will become trickier toward the end. You can push the bead with your thumbs or tire levers to make it fit. Sometimes this can take some muscle.

7. INFLATING. Once the tire is attached to the wheel, rock the tire back and forth looking to make sure that you cannot see the tube sticking out. (If it is and you didn’t check you will get a “pinch flat” as soon as you inflate.) Once the tube is up inside the tire, it is ready to be inflated. Look at the sidewall to find the recommended pressure or PSI. When inflating, make sure the tire is even and has no bulges or low spots.

8. INSTALL THE WHEEL. Put the wheel back onto your bike. If REAR wheel, ensure that you put chain back onto the smallest cog on the cassette (same as when you removed it) and then make sure that all gears are shifting properly again.

9. CONNECT THE BRAKES. Don’t forget this part!

*Want more information about Nutrition/Lifestyle/Cycling/Triathlon Coaching, or to join the Cycle University Multisport team – contact Mary Craig at Mary@cycleu.com.