How to Repair a Cut Bicycle Tire
- 1). Release the two brake arms on the wheel that has the flat tire. Caliper brakes work by squeezing the bike rim, but to take them off you need to squeeze both arms of the brake very firmly with one hand while releasing the coupling connection (it looks like a macaroni noodle) with your other hand by lifting up and out. Some brakes are equipped with a side pull lever that merely needs to be lifted to disengage the brake. Other types of brakes do not need to be disengaged at all in order to remove the bike wheel.
- 2). Release the quick release, which secures the wheel to the bike, by opening the lever and spinning it left at least five times. The quick release is located at the center of the wheel, the axle. If you do not have a quick release, you may need a crescent wrench to loosen the bolts that hold the wheel to the bike. Remove the wheel by pulling it down and away from the bike frame. If you are dealing with a back wheel, it might have a chain and derailer. Grab the derailer near its two visible gears and rotate the whole assembly backwards and as far away from the bike wheel's gears as you can.
- 3). Insert a tire lever between the wheel's rim and the tire and waggle it back and forth while pressing down in order to get it underneath the edge of the tire, which is called the bead. Once beneath the bead, insert another tire lever underneath the bead and carefully lever the bead over the rim. If necessary, use a third tire lever to get enough leverage. Once the entire bead is off of the wheel rim, pull the rest of the tire off the rim. Pull the old inner tube out of the tire.
- 4). Pump up the new inner tube, but only enough to maintain its circular shape. The tube should be soft and only slightly inflated. Nestle the new tube into the tire and then fit the tube's valve through the appropriate hole in the wheel's rim. Use the tire levers to fit the tire back onto the rim before inflating the tube until it is firm. Rotate the derailer backwards and out of the wheel before re-attaching the wheel to its original position. Secure the axle by spinning its quick release or nut to the right before re-engaging the brake. Finally, squeeze the brake levers as before and restore the coupling (noodle) or brake lever to its original position.
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