sluggish start

These bikes must be notoriuos for sluggish starts and electrical snafus. as old as most of them are go figure. my manuals says cleaning the commutator
on the starter as one cause of sluggish performance.
worn brushes is also a cause. HAS anybody cleaned these starters and had any luck. i think mine may be a short but i do have a local guy who re- builds starters and alternators. Plan on taking it out and let him look her over. I will let ya know what he says. grrr-grrr is getting me no where.