Originally Posted by boe1971200

Try this-
1) Turn the ignition on
2) Turn the kill switch on
3) Thumb the starter

If the bike starts the battery is ok, if not you need a battery. Hope this helps.

Originally Posted by Bluehighways

Take it to a Harley Dealer or an AutoZone, Checker, Shucks, Kragen, O'Reilly, etc. A Load Test is good, use of a Capacitive tester (Midtronics or similar) is slightly more accurate/predictive.

As YamaHarley implies/suggests; you can:

1. Disconnect the spark Plug Wires and (this IS important) use a couple of jumper wires to ground the disconnected Spark Plug Wires so that the bike will not start.
2. Turn every light on the bike "On."
3. Put a Volt Meter on the Battery.
4. Crank the engine with the Starter Motor for 30 seconds. (This is done to remove what is called a Surface Charge which can otherwise create a false positive result.) Note: 30 seconds is a long time so keep an eye on your watch. Do NOT short change the 30 seconds.
5. Wait 2 minutes. (This allows the battery to fully recover. Remember that a battery creates electrical power chemically. So give it a couple of minutes to reach/restore its chemical balance.
6. Crank the engine with the starter motor again for another 30 seconds. Again do NOT stoop short of 30 seconds.

A good battery should not fall below 9.6 Volts at the 30th second of the second time you crank the engine with the starter motor.

This test will not be 100% accurate, but neither (for a variety of reasons) is a Load Test. On the other hand, without a Load Tester (Carbon Pile) or a Capacitive Tester it'll be the best you can do in your garage at home. Also, FWIW, the (what are called ) Wienie Roaster type testers are of almost no value. Other than to the folks that sell them I suppose.

Originally Posted by JohnK-NJ

Thanks for your post. Could you tell me why I should groun the spark plug wires after removing them from spark plugs?

Originally Posted by RK4ME

That's a good "home" test - not so good in a parking lot, after dark, a long way from home.

Originally Posted by boe1971200

It was intended as humor and smartassness

Originally Posted by JohnK-NJ

... I was thinking maybe a test like leaving the lights on for 15 mins then trying to start it? ...

Originally Posted by Bluehighways

Also, FWIW, the (what are called ) Wienie Roaster type testers are of almost no value. Other than to the folks that sell them I suppose.

Originally Posted by jeffreydsilver

What you refer to as "Weinie Roaster" testers are the most common of all portable battery testers out there. No value? They give you a volt reading when the vehicle is at rest, while it's starting as well as when it is running (charging output). Most also give you the option of doing an independent load test also. The tester is relatively inexpensive and easy to use.

Now, I would agree that the results are only as good as the mechanic is at reading them!