I've got about 15 hours on the 14 yz250f and noticed the shift shaft has about twice as much slide play in and out as my 13. it's not the shifter lose on the shaft, its the actual shaft inside the case. I'm also having issues miss-shifting from third to fourth and "clunky" down shifting as well due to this problem. I'm going to tear it down this week to see if something may have loosened. it happened rather suddenly, it wasn't gradual. Anyone experiencing this issue? I assume all bolts are torqued to spec from factory but vibration and heat change may loosen some I've found, but I've never had this problem.