There is not a big diff, but there is less 71s than 72s I am thinking, and the flavor is older.
They may have 300,s (not sure)
have earlier style instruments, 1 year only, + painted ears
(72 has 1 year onlys, the best chrome ones IMO)
no dash, has clamps, , so looks a bit earlier, early type stripes on tank
no seat lock I think.
Just a bit earlier & harder to finder.. the later they got the easier theyy are to come by.