I'm trying to pump up my tires (natrually) . . . The hose end of the floor pump has a dual Sharder & Presta portion. For some reason air is only passing through the strader valve part of the hose end (which I never use), and not through the presta section. I need the presta side to work. I've used this pump dozens of times before, but right now there is no air blowing through the presta portion. I'm confused . . . what am i forgeting? I've never had similar trouble in the past.


It's a newish Blackburn 'TrackPump Sport 2"