A catheter shaft for a balloon dilation catheter to be utilized with a guidewire includes an outer tubular member having a bore, a proximal end and a distal end with a guidewire tubular member coaxially disposed within the bore such that the inner surface of the outer tubular member and the outer surface of the guidewire tubular member define an annular inflation/deflation lumen extending between the proximal end of the shaft and the distal end of the outer tubular member with a plurality of discrete, spaced apart legs extending radially outward from the guidewire tubular member that serve as a stop or stops preventing movement of the guidewire tubular member into the outer tubular member when the legs abut the distal end of the outer tubular member.
