ok i found that the gs500 uses a 7/8" bar but what is the rise,pullback, width, and center measurements?    im going with some aftermarket but i wanna pull them back some.   this is for my '89 build up

Doesn't quite answer your question, but the bikemaster superbike bars are the closest aftermarket bars to stock, i think and the specs on them are here
http://www.motorcycle-superstore.com/1/4/68/15394/ITEM/Bikemaster-Superbike-Handlebar.aspx

That should get you in the ball park, but I think they're a little shorter.