Of all the frames in my SBDU collection, this Track frame is by far the most fascinating and prized. An actual frame once ridden by Jan Raas. Raas was one of, if not the most famous rider to be part of TI-Raleigh. There is too much about him and his successes to list in this post, just have a look at his Wikipedia page to see what I mean.
Track 531 JR178T (Jan Raas) (1978)