The GL range (GL500, GL650), the CX500E Sports, the CX650E Eurosport and the Turbo models all shared the same basic frame layout, which was substantially different to the original CX500 frame. Here’s a photo of the later frame:
One of the most obvious differences is the lack of center spine; this one has a triple backbone running down the frame which splits off into two separate down pieces on either side of the bike:
If you’re planning on cafe’ing a bike and are chasing the empty-under-the-seat look this sort of frame will result in a different look. This frame came from the factory with a single shock absorber at the rear with a Pro-Link linkage system, with a beefier swingarm from factory to accomodate the single shock setup.
For pics of the single spine frame, see this page.