6865 Captain America!
6865 Captain America's Avenging Cycle is the smallest and cheapest (£12) of the Marvel sets. It comes with three figures, an 'avenging cycle', and some weaponry and contraptions for the baddies. The box doesn't give them a name so I have no idea who they are!
As you can see, the standard City police motorcycle is used in the set and when stood next to a minifig it becomes apparent just how ridiculously over-sized it is, what with the handlebars level with his head! Nevertheless, once CA is on it, it doesn't look too bad.
It's expensive at £12, but being the only set with Captain America in it, this is a must-have.