Bugger, probably a bit late this posting on the 15th, but never mind.
If it's not been raining (and the road crews arn't spraying water all over the place), I reckon you'd be able to manage the bypass track fairly easily. You certainly wouldn't want to be setting any speed records, but by taking it fairly steadily I reckon you could make it without too much trouble.
Just watch out for potholes when approaching some of the roadhouses, I cracked the frame on my XT by not spotting a big track-spanning hole in time.
(and that was one up)
Be aware that if it rains while you're up there, the return trip will be a completely different beast. It only takes a little bit of water and a few road trains, to turn what was semi-reasonable into a quagmire of slippery slippery stuff.