Originally Posted by
RobbieTunes
I have absolutely no idea.
It may be angles; I don't know. That stuff confuses me, so I stay away from it.
The only geometry information I found indicates the '87 has a head tube angle of 74 degrees and a seat tube angle of 73.5, which (if I understand the numbers correctly) would make it exceptionally steep and aggressive, even by today's standards. My guess is that if any angles were changed in '89 it would be a 74 degree seat tube angle, and I would also assume that these angles are what give the frame the unique riding characteristics that make it so desirable and fun to ride.