Patching a punctured inner tube

Tires & Tubes

1. 1

   A flat caused by a small puncture in a butyl-rubber inner tube is commonly addressed by patching, either with a vulcanizing patch and rubber cement or with a self-adhesive (glueless) patch. Patches are widely used because a typical kit weighs less than a spare tube, and a single kit can fix several punctures. Patching is most reliable when the puncture is small (a thorn, wire, or glass-shard puncture rather than a long slit), the area around the hole is clean and dry, and the patch is sized at least 6 mm larger than the hole on every side.

2. 2

   In typical roadside practice, the rider removes the wheel, removes one bead of the tire from the rim, extracts the tube, locates the puncture, applies the patch, reinstalls the tube and tire, and reinflates. The procedure below covers vulcanizing patches; glueless patches skip the cement step but otherwise follow the same flow. This pack is general reference and not a substitute for the patch-kit manufacturer's instructions.