A balloon catheter for use with an endoscope may have a flexible shaft extending between a proximal and distal end, with a hub affixed to the proximal end, and a balloon that is longitudinally asymmetrical. A balloon may have a central or cylindrical working portion, flanked by proximal and distal tapering portions, which are in turn flanked by proximal and distal balloon legs, which are affixed to the catheter shaft. In more specific detail, a longitudinally asymmetrical balloon may have proximal and distal tapering portions that have a relatively steep and a relatively shallow tapering angle, respectively. An optional additional feature of such a balloon catheter is that the catheter shaft may have a high pull strength and low longitudinal elongation, by including some type of reinforcement.