The butyl rubber compound that the Q-Tubes 650c x 18-23mm Presta Valve Tube is composed of is lightweight and offers protection from the elements. The threaded presta valve features a removable valve core making it easy to add sealant for even more protection while riding. The 650c tubes are available with a 32mm, 48mm, 60mm or 80mm valve length that will work with pretty much any wheel available. The tube weighs roughly 90 grams.
If you own a triathlon bike with 650c wheels, you understand that sometimes tubes are hard to come by. The Q-Tubes 650c x 18-23mm Presta Valve Tube Tube will make a great spare or replacement tube if you flatted your current tube.
The Race 28 700C Presta Valve Inner Tube from Continental is an all round innertube with standard rubber and thickness for durability and reliability. Available with a Presta Valve in 42mm, 60mm or 80mm long.
Presta valves are longer, skinnier and lighter than Schrader valves. They feature a metal screw-on top attached to the depressible valve pin, which protects the valve from leaking air. The Presta valve, with no internal spring, relies on the external air pressure being lower than the internal pressure to keep the valve closed. A new Presta valve inner tube comes with a cap similar to a Schrader cap. Bike mechanic Sheldon Brown notes that this cap's only purpose is to protect the rolled-up inner tube from puncture by the valve. A ring-shaped nut screws onto the body of the Presta valve and holds it firmly in place against the rim for easy inflating. Prestas are more common on road bike inner tubes, including sew-up or tubular models.
Continental Light 650x18-25mm 60mm Presta Valve Tube
Bikeman Product Code: TU9256