How about this great little bike sent in by Bob Decker. Bob describes it as a "speedway/boardtracker" that is "lottsa fun!". It uses a stock simplex frame and parts and has been bobbed and stripped to resemble an old racer. Bob replaced the old 2-stroke engine with a 200cc, 4-stroke continental slant square port engine coupled to a Comet torque converter and geared at 6.8. Bob apparently has lots of other homebuilt projects too... Hey Bob, whatya waitin' for? Let's see what else ya got.