I've got a 2006 with only about 12,000 miles on it. I've only had it about three years and bought it from the original owner. Oil and fluid changes have been done on schedule and for the most part the bike runs great. Love it.
Having said that, I've been noticing lately that I have issues sometimes when shifting gears. The gears change both up and down but I'm finding I sometimes need to kick it twice, or sometimes even three times, before the gear actually change. They change smoothly and quietly, it just takes a couple of extra toe kicks. It used to be sporadically but now it's more often.
I recently changed the motor oil and filter as well as the rear drive oil and yes, I used the correct oil as per the manual. The clutch cable feels fine but I'm wondering if they could stretch over time.
I live in a rural area and the nearest bike shop is a bit of a drive so I'm hoping someone here has any experience and might know if this is a fix I could do.