The Throttlebots added Goldbug in 1987, this was an upgrade of the classic Bumblebee character, maturing him and powering him up so he wasn't so much the Autobots' "kid brother" character. In the comics, this change was facilitated by having the G.I.Joe team blow up Bumblebee! Story continuity is an odd thing in that when Bumblebee came back to toy stores in newer incarnations, it raises questions as to what happens to Goldbug? In the IDW comics, this was sidestepped by having Goldbug and Bumblebee be separate characters.