Description
Genuine Yamaha OEM counter sprocket nut for the 99-05 and 06-13 R6 engines used throughout 600 micro sprint racing. This is the nut that retains your front sprocket on the countershaft, and it is not a place to run a worn or substitute fastener – if it backs off, the chain comes off, and the damage goes well past the sprocket.
Because it is the OEM part, the thread pitch, shoulder height and torque spec all match what the engine was engineered around. Aftermarket look-alikes frequently miss the shoulder dimension, which lets the sprocket walk on the splines and rounds them out over a season. We stock the factory nut so you do not have to find out the hard way.
We recommend replacing this nut and its lock washer any time the front sprocket comes off, and always after a chain failure. The matching OEM lock washer is available as an add-on option above. If you are freshening a chain drive package, this is a five-dollar part that protects a very expensive one.
