Hi Peter. The Automatic clutch is in effect, to a certain extent, self adjusting so it requires less attention than a standard clutch. While, as it has been said, these bikes are very robust, they don't have a large oil capacity in the sump, so regular oil changes are important, especially in hot weather. My guess is change with good oil, every 3-4000km. At high miles, the ramps in the clutch that the balls travel outwards and force the plates together can develop grooves which means the clutch does not dis-engage smoothly. The symptoms are the clutch not coming free when you come to a stop and the motor stalls. These can be dressed out with sandpaper or file if you are patient.
Nigel in NZ
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