Originally Posted by
Charles Wahl
"Champion" was a line of Tange (Japanese) tubing; though there are champions everywhere in the world of cycling, that's the only frame material one I know of.
"Champion" was also a line of lugs, fork crowns, and bottom bracket shells produced by Tange. The fork on the OP's bike is almost certainly a replacement.
I suspect the frame is an old Keirin frame that found its way over here.