when to rebuild

[Guest Guest]

has anyone had to rebuild there yamaha yet...

[GPS Dual Sport]

I have over 4000 miles on my 98 WR and only trip inside the motor was a valve adjustment at 800 miles. The exhaust valves tightened up to the lower end of tolerance.

I have heard that some YZ400's that have raced hard have problems with the small end bearing on the connecting rod.