There's plenty of bike racks that fit into a 2" receiver. Is that what you're talking about?
http://www.amazon.com/Allen-Sports-Deluxe-4-Bike-Receiver/dp/B001PLG7UK/ref=sr_1_2?ie=UTF8&qid=1376920681&sr=8-2&keywords=hitch+bike+rack
Or are you looking for something that would attach to a drawbar and retain the ball as well?