Valve stems are used on most tires -- from bicycles to large trucks -- to allow the tire to be inflated quickly and properly. Most problems with a valve stem on a bicycle or truck tire -- tires with Schrader valves can be used on both -- can be attributed to a faulty valve stem core. Rather than replacing the tire or having a tire or bike shop make this repair, do it yourself in only a few minutes with an inexpensive tool that can be bought at most automotive stores.
Remove the cap from the valve stem and press the tip of the core down with the screwdriver or the tip of a nail to release the air pressure.
Place the valve stem core removal tool into the stem and over the core. Turn in a counter-clockwise direction to loosen the core. Lift out the core removal tool and remove the core.
Place the new stem core into the end of the removal tool and place it into the stem. Screw into place by turning clockwise with the valve core tool. Tighten completely but don't overdo because you could strip the valve core threads.
Pump the tire to its recommended air pressure and test for leaks. Mix water and dish soap in a spray bottle and spray the mixture around the stem. Check for bubbles, which indicate air escaping from the stem. If the stem is leaking, tighten the core again and recheck for leaks.
- Remove the tire from the bike if needed to access the valve stem easier.
- If the leak continues after retightening a new stem core, the tire's inner tube may need to be replaced.
- tyre valve image by TA Craft Photography from Fotolia.com