Do you ever wonder how long the 690 will last ?
There's no reason it couldn't last 50k but the question is how much work would be needed to get it there. Top end refresh maybe...Hmmm. Tricky one. I don't honestly see it being a 50,000 bike, but I'm not a 50,000 a year rider either.
50k has been done by several owners of DRZ400's, in fact I think the records stands at something like 100,000 miles on a stock un-opend engine.
..and 50K miles is not even worth mentioning in the KLR650 crowd.
Most would give the engine a new cam chain at 40-50K miles as insurance. Other than that it's just regular servicing, as long as the bike hasn't be tracked every other weekend it should be fine.
Resale value though... nope...
I was looking at Fireblades the other day and saw one with just over 30,000 miles on it and thought nope.. too high.. yet my hornet had 24k on it and my SD is at about 19k now.
It is strange how we view the mileage on bikes, but the market is what it is.