It currently has 37,000 miles and has had oil changes like the book said. Its always been synthetic oil. I'm curious, as long as i take care of it, how much longer does it have?
I have an 89 883 (well really its a 1200 now) but If you stick to the maintenance it could last over 80,000mi before a rebuild would be necessary, or more if your not bashing on it. I mean rebuild though, not buying a whole new engine, there isn't that much to them.
You should be able to get a good 80,000 mikes out of it before it needs new rings and a top end job. Many last well over 100,000 miles when ridden and maintained with care.