Device to dismount a tyre form a rim having outward sloping seats

The tool consists of a curved insert (4) with a narrow triangular cross-section that lifts a tyre bead so that its seat is in line with the raised edge of the wheel rim. The surface of the tool in contact with the bead seat has a groove that keeps the insert engaged with the bead as it is inserted between it and the rim. In variants of the design the groove can be replaced by a gap between two rows of protuberances or rows of cavities (421, 422). The middle of the tool has a transverse extension (51) to protect the edge of the wheel rim.