Before putting the tube back in, run your fingers carefully along the inside of your tire. If the thorn, glass, or wire that caused the flat is still stuck in the tire, it will pop your newly patched tube instantly. When to Toss the Tube
Spread a thin, even layer of the fluid over an area slightly larger than the patch. Wait 2–3 minutes. The fluid needs to be "tacky" or nearly dry to the touch before you apply the patch. Bicycle Inner Tube Patches
These are essentially heavy-duty stickers. They are incredibly convenient and fast, but they are generally considered temporary. Over time, the adhesive can dry out or peel, so they are best used to get you home. Before putting the tube back in, run your
Pump some air into the tube. Listen for a hiss or feel for airflow. If you’re at home, submerge the tube in water; a stream of bubbles will pinpoint even the tiniest "slow leak." Wait 2–3 minutes
Here is everything you need to know about bicycle inner tube patches. The Two Types of Patches
This is the most important step. Use the small square of sandpaper in your kit to roughen the area around the hole. This removes the slippery molding agents from the factory and gives the cement a textured surface to grip.