Nice bike and beer choice. I just hit around 4500 and the rear brake just hit the end of its adjuster, the fronts are ok. For service i drip something like 3-in-1 oil and powdered graphite down the brake cables like once a year. and electrical tape up the spots where the plastic jacket wears thru from chaffing.
in the clutch i cant give ya a good idea when because this was my first moped like 10 years ago and i like tinkering with it alot n useto break stuff hah.