G'Day Derek, your Suzy is looking very nice mate, well done! Re: your carbs, I'm presuming that your airbox is installed with a new air filter, and everything is as it left the Suzuki showroom floor, yeah? As I've said previously, Mikuni CV carbs are much more sensitive to adjustment than our Keihin carbs.
Take your tank off and (installing longer fuel and vacuum hoses or using a dummy tank and plugging the vacuum hose connection between carb #1 and #2) run the engine at idle. Your mixture adjustment numbers are "ball park" at best, so with the engine idling (and if it's warm, with a fan blowing over the engine) in a well ventilated area, while watching your tach, slowly adjust your mixture screws in or out until you see the idle increasing, then keep adjusting them until you get a nice stable idle.
Unlike the idle circuits on Honda carbs, Mikuni CV's idle adjustment affects the bike's preformance regardless of throttle position, so if it idles like crap, it'll run like crap right across the rev range. Also, noting how blued your header pipes are, check your ignition timing, and don't assume that the ignition itself is not at fault, the igniter boxes in early GS bikes are known to work sporadically with age. I think they still offer alternatives to the OEM igniter box on The GS Resources website. How's your charging system? If your alternator isn't putting out at least 12 volts, your bike will run like shiite. Also, new plugs and caps are critical on these old bikes. Once again, well done mate, your bike looks great.
