The sports wheelchair includes a one-piece, welded tubular frame assembly (A). A pair of rear wheels (30) are horizontally and adjustably positionable in a rear wheel mounting plate (34). The mounting plate has a plurality of slots (36, 38, 40) and a plurality of alternating ridges (44) and valleys (46)...http://www.google.de/patents/US4500102?utm_source=gb-gplus-sharePatent US4500102 - Sports wheelchair
