The odometer never worked on the Pulsar when we bought it and it was registered with unknown mileage. The speedometer and trip meter functioned, so I knew I had a chance of fixing the problem.
Removing the gauge cluster on a Pulsar NX is not terribly difficult. Remove the steering column cover, the cluster bezel and the switch pods will give you access to the cluster.
Removing the speedometer also was not difficult after unsnapping the Lexan cover and unscrewing the corresponding screws in the back of the cluster. Once I had the speedometer pulled I could see the issue: the first odometer gear had a broken tooth and would not engage the drive. To fix this I removed the odometer gears by gently opening the metal brackets at each end, you can do this with a small screwdriver and pry the two prongs apart. I then removed the broken gear and "sacrificed" the six digit of the odometer by shifting all remaining gears towards the drive gear.