Tapered Hand reamer works for me, then rat tail files to take off burrs..
I think one of the wheels actually has an insert that the Presta feeds through, I wonder if I take that out if it's then the same size as a Scharder tube's valve.
Oh the wonders in life are many..
I got a trekking bike, its schrader drilled rims , came with a Mavic made adapter & P/V tubes..
the idea you are ready to use either type of available tube..
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