1 Prepare for safe work
Place the bicycle stably, clean the work area, and photograph the position of washers and cables before removal. For an electric bicycle, turn off the system and remove the battery.
⚠ Warning: Do not use a metal screwdriver as a tire lever; it can damage the rim, tire, and inner tube.
2 Remove the wheel and one side of the tire
Release the brake if necessary, remove the wheel, and use plastic tire levers to pull one edge of the outer tire out without pinching the inner tube.
3 Find the hole and the cause
Slightly inflate the inner tube and submerge it section by section in water or listen for hissing. Carefully run your fingers along the inside of the outer tire to check for a thorn or glass.
4 Glue the patch and put the tire back
Dry, roughen, and apply glue according to the patch kit instructions. Once it becomes matte, press the patch firmly, slightly inflate the inner tube, and put it back without twisting.
? Tip: Photograph the initial state and change only one thing at a time. This will let you know which check really affected the problem.
5 Assemble, test, and set limits
Spin the wheel and drivetrain by hand, then do a slow test ride in a traffic-free area. Brakes, wheels, and steering must function completely predictably before normal riding.