I think you're fine. The advantage to the 1200 is that is has better gearing ratio for speeds and rpms like that, so I feel like I have a lot left at 75. I dont go any faster though, because I'd like to live to see 75.
On a Florida Interstate better have the Power to hit 85 in a Hurry to avoid being run run over by some blind Q Tip Bluehair..
Well, my 1200R turns 2800 rpm at 60 - I know 883s are geared a bit lower, but 2800 is nothing - it would go 130 if it weren't drag-limited - stock.
I would say No Big Deal. 900 cc is not a small bike. I used to ride a 450 twin that fast for hundreds of miles with no ill effects.
It may be bad for the rider, but not the bike. I wouldn't know about being bad for the rider though cause I do over 80 almost every day. 8k miles this year, no problems.