If you have an HD starter you can sometimes get parts to fix it from a cheap Nippondenso starter found on Toyota cars and trucks. The idler gear and retainer for a Shovelhead starter can be had from an alternator and starter repair shop for around $10.00 compared to $47.00 from the aftermarket Harley catalogs
When your Shovelhead starter sticks, try removing the solenoid and flip over the big contact plate inside there. It will give your starter new life. Cleaning the contact plate will also help.
If you notice you are losing power on the top end or your bike stalls, pops, sputters, etc. when you are cruising, make sure you don't have 2 fuel filters inline. Your tank most likely has a filter in the petcock. If you add a second filter, the gas cannot flow through both filters fast enough to keep your bike running at high RPMs when the tank is less than half full.