After going over everything, it seems the rattle is deffinately primary chain, and no doubt caused by the carbs being out of balance.
Tried using my single gauges, but the one i used to use is broken, and the other old one i found fluctuates wildly. As its the type you press onto the carb instead of the air filter, there is no damping it.
So, ill be buying some gauges then.
I see a few of you like the carbtune ones.
Ill look for them.
What are the cheap 4 gauge ones on ebay like? Cant argue with 40 quid LOL.