VALVES EXPLAINED 

Presta/Sclaverand/SV Valve

Racing bikes, high-end trekking and mountain bikes are often equipped with the presta valve. The upper knurled nut has to be unscrewed before inflating.

Schrader/Auto/AV Valve

The robust auto or schrader valve is deployed mostly on mountain bikes, for inflation, the pump has to be pushed on the valve as far as possible for pushing down the air release pin.

Dunlop Valve

The classic bicycle valve (dunlop) is still widespread in many parts of the world and found mostly on city and favorable trekking bikes.