Motorcycle Repair: starter solenoid 1979 FXWG, starter solenoid, starter shaft

Question
Have a 79 FXWG...got it with this problem.....hit the starter switch the and it engages ...the motor turns and when it fires you can hear the starter gear grind and bang...removed the primary cover to inspect....the needle bearing in the cover looks fine...the small gear on the starter shaft shows a little damage....the shaft seems to have alot of play..I know the shaft rides in the primary cover and that bearing supports it.....SO what do you think...can the solenoid be bad in that it is not pushing that gear fully out ?? this must be somewhat of a common problem..if it's the solenoid ..is it beter to replace or rebuild...aftermarket O.K.  ?? thxs AJ

Answer
The shaft itself might be bad. You need to pull it and inspect it. Its probably not the solenoid, since it always goes out all the way because it nothing but a big magnet. Also, if your timing is advance to far that will caure the banging
Happy Menorial weekend
Mike