Tips on troubleshooting starter

[Pedro-bot]

Patient: 2002 S4
Mileage: 11k
Chief Complaint: Starter won't engage, engine won't turn over
History: Charged up my battery after it went dead from no use over the past several months. The bike started up great first couple of times. The 3rd or 4th time I started it up today the starter made a "pinging" noise. The motor does not turn over and it sounds like the starter sprag is jammed. The pinging noise does not sound like the sprag is freely spinning, rather it sounds like it's jammed and can't turn the engine. The battery is fully charged and is not an issue of a dead/poorly charged battery. Anyone have any ideas on how to approach this? Pretty safe bet to remove cases, starter and replace starter sprag?

[Howie]

First, have the battery load tested.  A fully charged battery is not necessarily a good battery.  If the battery has not been charged while the bike was in storage it has suffered sulfation.  Then try applying battery power (with a good battery) directly to the starter motor (make sure the bike is in neutral since you are bypassing all safeties).  If the starter now works you have some troubleshooting to do in the control and ground circuit.  If the starter does not operate, remove it and see how it works without being installed.  Then lookk at the sprag.  Simple, easy, cheap first.

[DarkStaR]

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Then try applying battery power (with a good battery) directly to the starter motor (make sure the bike is in neutral since you are bypassing all safeties).
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+1; however, this is usually my first stop when trouble shooting the starter just because it's so easy to get to.