Jim - I have an odd 87 with a sloping fork crown (not like the 87 catalog pictures) and an extra long top tube (58 cm top tube on a 56 cm frame). I have never seen one from this period with a headbadge. I am sure you already know that SLX started in 86 and the chrome chainstay ended in 87 (I think). Although it may be hard to tell from the picture, the yellow looks like the 86 brighter yellow, the 87 yellow was a darker and richer. What does the seat lug look like ??