Loosen the axle.
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Go to - ZX1000 A1 - Swing Arm
Loosen the pinch bolts at the rear of the swing arm (both sides - L&R) #92002
Using allen wrenches, turn the axle sleeves #42036 the same amount at the same time.
The holes that the axle goes through are offset.
When the axle sleeves are rotated, the axle moves forward and back depending on which way the sleeves are turned.