not too sure about these clutches but on most clutches the pads will glaze over and you can sand the glaze off and it'll be back to gripping along with spraying down the entire assembly with brake cleaner to get all the clutch dust and debris off. you can also do this with the clutch drum lightly and evenly by wrapping your clutch disk in sand paper then spinning the disk on the drum. wanna watch out for any rainbow or blueish colors on the drums clutch surface cuz those are hot spots which will eat a clutch in no time. you get those from not properly breaking in the clutch.
like i said though not sure if this apply's to these midbike 4 strokes cuz i heard they use a wet clutch. this explanation is either for a car or 2 stroke pocketbike and of coarse its a lot harder to do on a car which is why you always break in your cars clutch correctly!!!!
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