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the keying you found on your Falcon's steerer is one of several types employed in the industry

this is considered a flat and there are steerers which receive the flat on the front, mostly British products, steerers which receive the flat on the rear, mostly French products, and steerers which receive a rectangular slot keyway, usually on the rear but occasionally on the front of the steerer

Weinmann, for example, offered their front brake hangers for their centrepull brakes with flats on the front, flats on the rear, a tooth on the rear and a tooth on the front


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