nw rain man

Another ignition timing question ! I acquired a model 191 Sherpa 350 which appeared to have minimal hours. Needed TLC with a standard piston ( piston / cylinder tolerance of .004.) Cleaned up the bike and carb and put in new set of rings. Getting ready to start but first checked the points and timing. ( Bike ran when purchased ). Points within spec - .016 but when checked timing , I found the BTDC was 6 mm ! Can this be given that the bike nan prior to purchase , even rode it up the street. Am I miss something . Here are a couple of pictures . Any help would be appreciated...