Provided is a dual lumen aspiration catheter system with an aspiration catheter, a hub and a flexible strain relief, and a suction assembly. The aspiration catheter includes multiple successively connected flexible tubular components each increasing in relative flexibility in the distal direction, the most proximal tubular component connectingly extending from the hub and through the flexible strain relief. The tubular components of the aspiration catheter include, in order proximally to distally, a composite tube, an intermediate tube, a dual lumen tube, and a flexible tip tube. The dual lumen tube includes eccentrically co-located large and small tubular portions forming eccentrically co-located large and small lumens to provide a minimum cross section. The distal end of the dual lumen tube includes a convex beveled edge. The convex beveled edge and the flexible tip tube singly or jointly inflict minimal traumatic contact with a vessel wall when urged along a tortuous vascular path.