...it's a Super GoBot!
Cy-Kill to be precise.
Although GoBots were well known as predominantly 1:64 ish scaled vehicles/robots, a handful were produced which were much larger and more in proportion with their major competition, the Transformers.
Both the Guardian leader (Leader-1) and Renegade leader Cy-Kill were produced as Super GoBots during the series' short run.
Cy-Kill, as his name implies, transfo...I mean Goes from Bot mode to Motorcycle mode. The Super GoBot version differs from his mini version in that his wheels and engine are integrated and do not detach from Cy-Kill at all. While this is an advantage in that you do not have any extra parts to keep track of, it detracts a bit from his design - part of what made Cy-Kill look so cool in robot mode was that his wheels were held on his shoulders.
Cy-Kill is pretty solid, with his torso/head being die-cast metal and the tires being made of rubber. His "change" is simple but effective, and of course his old school Japanese giant robot design is quite groovy.
With GoBots recently on my brain, I guess it shouldn't surprise me that I found him at the swap meet today, but good golly miss molly I nearly lost it when I stumbled onto him! I had the small Cy-Kill when I was a kid (and he had the green/grey/black color scheme) so although this one is a little roughed up, he's a great find and in good enough shape to happily be added into my slowly rebuilding GoBot collection.