I want to get an idea of my batteries strength. Anyone have a test to gauge a battery's condition when you don't have a load tester? It's in my 2002 Fat Boy. I was thinking maybe a test like leaving the lights on for 15 mins then trying to start it? Or some test with a multimeter? Any ideas?

 

Your bike is a load tester. Put a voltmeter on the battery terminals with the bike turned on, what's the voltage? Now hit the starter, what's the voltage? With the starter engaged that's under load.

 

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.

 

I saw on YouTube to start the bike with voltmeter hooked up and make sure voltage doesn't drop below a certain point, forget the exact voltage. Mine passed but I had auto zone do a test anyway which it passed. No idea if there is a correlation but easy test in the garage.

 

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.

 

Yammy is right.

Here's a cheap load tester. Plug this into the Battery Tender lead and hit the start button.

http://products.batterytender.com/Ac...D-Display.html

It also fits in the tool kit nicely for on the road diagnosis.

 

Take the damn battery out and run it down to the auto parts store.

rk classic.

 

Put your tongue on it.

 

I use one of these on all of my 8 batteries. Better than a load test for determining condition. Lots on Youtube on how to use it : https://www.walmart.com/ip/SOLAR-BA7...&wl13=&veh=sem

 

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!