Protection apparatus for a speed change mechanism of a bicycle or similar vehicle

摘要

Protection apparatus for a speed change mechanism mounted on a spoked rear wheel of a two-wheeled vehicle. The speed change mechanism includes a roller assembly for shifting a chain transversely to effect speed change. The protection apparatus comprises a counter-flange on the roller assembly disposed between the rear wheel and the roller assembly, the counterflange having a peripheral edge with a plurality of bend regions at locations where the counter-flange could contact the spokes of the wheel if the roller assembly were excessively displaced. The bend regions are bent in a direction away from the rear wheel to prevent insertion between the spokes of the rear wheel.