Try putting your FA mixture screws at 2.5 turns out and see if that helps.
Don't give up. Do you have any idea what condition the carbs were in when you got the bike? How long had it sat?

 

Hi matey keep the faith, might have to play all in here, how about taking off the carbs , compression test , carbs cleaned back on, all other air pipes off (except carb only pipes) Auxiliary petrol tank straight to the carbs and get the engine running well ,then start building all other pipes back on see where any fault is springing from and sort that, could otherwise keep going round in circles, what you think?