Bicycle valves are a subject that tend to cause a certain amount of confusion, so it can be useful to know what type of valve you have before replacing an inner tube. There are three main types. Presta (racer valve), Schrader (car-type valve), Dunlop (Woods valve). Presta valves tend to be used on more advanced road bikes that have a high tyre pressure. They’re also the easiest ones to pump by hand. The valve core can be replaced on some Presta valves. They can be pumped using the same type of pump as for the Dunlop valve. However, they cannot be pumped with normal car pumps, so you can’t simply cycle into a petrol station to inflate your tyres. Adapters are available to solve this problem, but you need to remember to carry one with you. You can change from Presta to Dunlop or Schrader valves if the rims are sufficiently wide to enlarge the hole. The Dunlop valve is the type that used to be used on most bicycles. If you’re old enough, you probably remember the valve rubber that sat over the core – the little piece of rubber hose that tended to dry out and crack after a while. Valve rubbers used to be included in all bicycle repair kits. Then valve cores with valve rubbers were replaced by the maintenance-free type we have today which has a little ball as a non-return valve. The valve core can be replaced. They can be pumped using the same type of pump as for the Presta valve. Schrader valves are the type used on cars, so it’s easy to find a pump if you need one, for example at a petrol station. The valve core can be replaced. These are common on mountain bikes, but also on “normal” bicycles. You can replace a Schrader valve with a Dunlop valve, but if you want to change to a Presta valve you need a small adapter to reduce the size of the hole in the rim.