I have an 05 yfz450, it was put away running 9 years ago. I brought it back out, changed all the fluids, cleaned the carb, and it will start with some ether but revs high and then dies. Not sure where to look next
high revving is usually lack of fuel or too much air. Might need to double-check the carb boot and hoses on the carb..... and possibly reclean the carb again. Don't underestimate the tiniest bit of crap possibly getting sucked through the system.
I just bought a used 2016 Yamaha YFZ 450 R a few days ago. It’s practically brand new less than 20 hours on it. I noticed the light knocking noise in the motor is that common on these machines? That’s kind of what I’ve been hearing.