I think it is Hideki Kanazashi, too, since his first game was around 1986. I am also thinking Hiroaki "GSX" Suga had something to do with the original Mach Rider. Probably something along the lines of sound effects or sound programming. Not to change topic here, but whoever composed Mach Rider probably also worked on F1 Race. They have similar tunes. I don't think Akito Nakatsuka worked on the music because he usually composes jazzy-like music.
I was told by Shogo Sakai that Hirokazu Ando did not compose Mach Rider.
UPDATE:
The composer is definitely Hiroaki Suga:
http://www.vgmpf.com/Wiki/images/0/0...igh_Scores.png
GSX is an alias for Hiroaki Suga.