On this page we attempt to make available the experience of individual bicycle tourists who have travelled with China Eastern Airlines (you can share your experiences here).
China Eastern Airlines
Had no problems with a tandem unboxed. A man was assigned to wheel it off, and it was returned undamaged at Xi'an airport without problem.
We were flying on a Boeing 737. No extra charge. The only difficulty was fitting it in the Xray machine - just needed a bit of dismantling.