My canned rundown

After a good 24 hour low amp controlled charge and the battery has set about 2 hours voltage should be about 12.8 volts.
12.8 = full charged
12.6 = 75%
12.3 = 50%
12.0 =25%
With a DC volt meter (that has a feature to lock high and low reading) hooked across the battery terminals and reading 12.8 or so, crank motor and while its cranking it should not drop below about 9.6 volts and as soon as it starts and throttled up to 2000 rpm or so should read around 14.8 volts. The crank check shows a rough check of the reserve amperage capacity of the battery while cranking with a 150-200 amp load on it. The 14.8 shows a good alternator and if you leave it on a while as the regulatory will drop the voltage a little showing itself working. However, with the lights and stuff always on it will never drop back much.
When a battery wears out a good charge will show fairly good voltage, but the battery can still have very low amperage capacity which will show in the crude crank test above, but it really should be checked after a good charge by removing it from bike and getting a free check at a place like AutoZone that has a fancy load meter check that gives you a print out of the battery health. Battery MUST BE CHARGED to check it. Be sure they set their meter to correct cold cranking amperage stated on the battery. Never charge the AGM absorbed glass mat battery with a regular car battery charger. Also by taking battery out you know you have good connections. Vibration tends to loosen the connections or a little corrosion will prevent charging or cause starting problems. Using the maintenance charger can get 5 years from a battery but be careful here. You do not want the last start 5 miles from home. If it still grunts when you first hit starter or kicks back, replace it. After a few years, charge and pull battery and have it checked for cold cranking amperage ever spring. If they have one, Wal-Mart's AGM absorbed glass mat battery is just as good as any one's for half the money. Do not jump, push start or run bike with a half dead battery except in an emergency. It will kill alternator stator or the voltage regulator or both. Probably a $500 repair.

 

Thank you again for the great info on that charging system!

 

One quick way to check your battery connections is to put a meter on the battery posts and read the voltage. Then move your probes to the cable ends. The reading should be very close. If it is not you need to clean the connections. You can expand this test to the other ends of the cables. Checking the starter post and then the cable end. Also at the ground connection. Hope this is of some help.