smokey 12HT cruiser

You say that of the start of your message that it is a 12 HT, but then say that it is a 2H, which is it, as they are totally different engines. Very smokey meaning blue or black smoke. Even if it is blue smoke it could still be a turbo problem or it could be blow by and oil being sucked from the rocker cover in to the Turbo.

no 2 eh from exp I'd just about bet my house that it has been cooked and has broken rings in no 2 cyl. More than likely no's 5 & 6 are on their way too. Sorry.

Sorry mate, she's stuffed. The only additive that is going to work is a cash one. Not a cheap option, an engine rebuild will cost between 3 to 5 thousand plus an injector & pump service.
DO NOT i repeat DO NOT skimp on the pump & injectors as they will place too much fuel into the cylinders washing the oil from cylinder walls causing your nice new engine to self destruct & you will be back where started.
Im sure you would not like to do it all again 20000k's later.
If you have any more questions email me at karl.brown@act.gov.au