I have 2 used ones for sale near me. No hour meter on the 2015 but was only trail ridden and appears low hours. The 2017 has 41 hours and was raced a few times. Owner also has a YZ250X that gets most of his race time. Both bikes stock. There is only $500 difference so I am leaning toward the 17. I like the idea of kick start for backup though. Not sure what the kit start kit for 17 would cost. Other than that it appears the 17 to be the better choice. Larger front disc, engine diagnostic light, factory skidplate, and whatever aledged motor upgrades. I rode the 17 and instantly wanted it. they are both priced high for the market but both are at a dealer. I may trade in a WR250R to save some hassle. Both bikes looked maintained well. So my question is regarding the 41 hours on the 17. Is that a lot of hours for piston and rings? Or better question, with proper maintenance what is the average top end repairs needed on these bikes? The test ride sold me on the bike.