A suspension unit is disclosed comprising: a hub 6; a bearing sleeve 24 eccentrically mounted within the hub 6; a crank pin 22 rotatably received within the bearing sleeve 24; and a connecting rod 20, a first end 28 of which is connected for rotation with the crank pin 22 over a connecting area 26 that comprises less than a complete circumference of the crank pin 22; the bearing sleeve 24 comprising a slot 52 through which the connecting rod 20 extends from the first 28 end to a second end.