hi i have a swinging arm with a WP piggy back resevoir monoshock and a leading shoe rear wheel. looking at pictures on the site i THINK it is a circa 1983 item. it has what looks like 300 or 500 pro lever marked on the side. i also have a set of WP USD forks and triple clamps which might be from the same bike. if anyone can give me anymore details or if anyone would be interested in buying either front or back end let me know.