You have to pick your body carefully.
His bottom half is a metal veteran, chopped just above the waist. His utility/batman belt hides the join. The top half is assembled from a regular marine torso, decked out. I can attach him to a bike, but he'll be riding no handed.
You could aim for something similar, but you would need to disguise the join when he's on foot. You can then take the torso and mount it on a marine bikers legs. You may also want to magnetise one arm to swap out for a bke arm so he doesn't look quite so evil kinevil.
That's as simple as it gets. If you want frills, maybe have a look at some ravenwing models, and use thier legs for the biker captain.