I remember being incredibly excited for this film in the lead-up, and ultimately very disappointed when I finally saw it. It was the (rather big) summer of 1989: Batman, Lethal Weapon 2, IJ and The Last Crusade, Ghostbusters II, Honey I shrunk the Kids, and Star Trek 5. ST4 had been such a huge hit, and this trailer played well.
The summer of 1989 was a very exciting time to be a teenage movie buff. In addition to all those, we also had Karate Kid III, The Abyss, Licence to Kill, Weekend at Bernies, Turner & Hooch, Parenthood, Uncle Buck, Friday the 13th VIII, and Nightmare on Elm Street 5 all opening in close proximity. (Not to mention some of the more adult titles like Do the Right Thing, When Harry Met Sally, or Sex Lies and Videotape.)
Star Trek V wasn't the only dog in that pack - nor even the worst of them, IMO - but for a movie-obsessed kid with a lot of free time available and a multiplex within biking distance, that summer was glorious.