My bike started using oil at around 16000 km , and the agents replaced my barrel a,pistons and rings at 32 000 km,
I have since put red rubber grease on the LH and RH Air filter side covers , I have fitted the YZ 450 Quad foam filter over my DNA filter to ensure no dust enters the box.
The air filter box drain pipe is too long , it catches on any bush or rock you ride over and either pills the blank plug out or splits the pipe when a rock squashes it against the frame , solution , cut it shorter , fit a 8mm bolt as a plug ans a decent hose clamp.
Finally , I dont get anymore dust in my air filter.
PS , I did 74 000 km on my previous XT660R with no problems at all.
So I know these motors rock !!!!