I have not read the manual for the 650. Um, nor have I fully read the manual for the 950, (my bike). But I want to say, Yamahas like to rev!! Not only is that something that I've heard/read, but I tested it when I recently crossed the country.
I was traveling for days on 80 mph highway that everyone goes 90 on.... - And my bike did fine. Top of its game, yeah. But no engine proplems. Don't forsee any, nope, nope.
Change oil, keep engine tuned, and rev the !*×#! Out of it!
Keep moving, learning, loving, and living.