You'll find that the CX/GL500s are a much underestimated motorcycle.They were innovative at their time of inception.Honda learnt many things from them that they used and still use in ther more modern motorcycles and they are soooo.... easy to work on.
Correctly set up they handle way better than people think.I have quite often ridden with some smaller Harley 883s and they cannot match a naked CX500 for handling and acceleration and power up to say 70 Mph which means for all smaller roads and legal limits I can blow them away.Then of course I still get better fuel mileage<grin>

Not to mention the Classic CX phrase you will hear,"I used to have one of those".
On a personal note there's not a lot I don't know about these bikes as both my CXs have basically been reclaimed using spare or refurbished parts and both my present running engines have been re-built by me from the crank-shaft up.
One of the cheapest and best things you can do is to change the weak ATF fluid used in the Forks for heavy 20w Fork oil.
http://cgi.ebay.com/ebaymotors/Motul-Fa ... veQ5fToolswhich you may have around anyway.It totally changes the handling and feel of the bikes.Mine are so solid on corners/bends they remind me of my old Norton Dominator 88 which had the world famous ,"Wide-line Feather-bed" frame of yesteryear and to quote the old reviews of those bikes,"It's like cornering on rails".