mmm – still no clearer, anyway.
mmmm – I think you are mismatching components. I have a old fashioed hand pump (handle/up and down in small cylinder job – no levers – you know old codger on bike long metal job – type that fits between two sticky out pins on a frame ). It comes with a rubber bit that screws into the end of the pump and the other end screws onto a schrader. I **think** the bit you are talking about is designed to fit on here to convert this to a presta (I have one of these and it works) – you screw it onto the rubber bit end and it 'changes' it from scharder to presta.
It sounds like you're trying to use it on a track pump – I have one it has a schrader head – and chained to that is a (much larger) adapter that can be cam locked to the schrader fitting to turn it into a presta.
It shuld work on the normal pump with a flexi rubber screw fit. On the track pump I doubt it. I **** THINK******* that the isssue is that when you use the cam thta pushes a pin forwards (on a schrader this would be to compress the valve core) and it sounds like thta it hitting the presta relesae but that there is not a good enough fit somewhere.
My guess it that that you need a track pump specific adapter (OR use lots of tape etc to fix the seal that is leaking ?????????
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