In the letter pages of Avengers #7, a question was posed as to whether the Avengers would add any members of color or any gay members. The reply was "There's always a chance. Heck, come back next issue." Avengers #8 was the debut of Triathlon.
This led to rumors, naturally enough, that Triathlon was (or at least was MEANT to be) gay.
Kurt Busiek cleared up this rumor at the Gay League,
We hadn't established anything about Triathlon's sexual preference, so when people asked about the possibility of a gay Avenger, I thought that hey,maybe he's gay -- we haven't said one way or the other. But Tri was so controversial, and so many fans had issues with how he got onto the team, or the racially-charged atmosphere it happened in, that I just didn't want to add one more aspect that would be a hot-button issue -- negative or positive -- with readers. Too many readers already thought of him as a token, so I thought it'd be better to work on getting past that than give another set of readers a reason to see him as a label more than as a character.