I've encountered another mystery with my 1976 CB500T. I installed a brand new throttle cable and have found that the I'm not getting a consistent idle. I set the idle at 1200 but the bike actually idles at anywhere from 1000 to 2000 rpm. It seems to idle on the high end after taking the bike out for a long ride at speeds over 50 mph. When I do come to a stop the tach is reading around 2000 rpm. Occassionally the idle will mysteriously drop to 1000 for no reason. At this point the bike wants to stall out completely. I made sure the throttle cable is routed correctly and have adjusted it to the specification listed in the book. Turning the handle bars one way or the other doesn't affect the idle at all. When the bike is idling high I made sure the idle adjustment screws were completely down (throttle not hanging up). Any help would be greatly appreciated.