A friend recently had an issue with the transmission on 15 YZ450. To cut a long story short, complete new transmission is required. Yup, it sucks.
We were thinking of putting in the WR transmission as it may be better suited to the terrain we ride - got to get a complete new one anyway. I understand there are a few folks who have done the same on rally bikes. I saw the threads on older models swaps/hybrids, but wondering if anyone had info on 2015s. Are the parts interchangeable, any other considerations? Also, do they sell these in kits vs buying each part separately. I was looking through the parts database, and it all seemed to be individual parts only.