Batteries

Many thoughts on batteries for the harleys, here's a few that seem to be coming up on the forum lately with batteries.

Never assume that if you measure the voltage in a battery and get 12+ volts that all is good with the battery. You can measure the proper voltage and still the motor will not crank.This has caused many to spend lots of time chasing a ghost when the problem was the battery. The reason for the false reading could be internal plate problems that will not carry the load (amps) needed to properly crank the motor, instead you may get a slow crank or even a click with the associated dimming or outage of the lights.
Always do a load test on the battery to be sure of the actual condition of the battery. Most auto parts stores will do this for free.

Another thing to remember when replacing the battery is most batteries in normal service that are installed in a bike that is ridden regularly will usually last approximately 4 years. Some go longer and some die prematurely from sulfating of the plates due to inactivity. Batteries need to be discharged a bit from starting and recharged from running in order to keep the sulfate off the plates. A battery in storage for extended periods will sulfate heavily and will usually not start the motor when needed. Sulfate can sometimes be removed by a low amp slow charge of the battery.

New batteries (replacements) should be of the same CCA (cold cranking amps) as the one it is replacing. If you can fit a bit larger one in the battery compartment, go for it. That means more cranking amps in the colder temps, it's a good thing.
All NEW batteries should be trickle charged to full capacity before the first use. This will give a bit longer life to the battery and eliminate the excess charging by the charging system in the bike.
The charging system is meant to maintain the battery and is really overworked to charge up a half charged replacement like most batteries that are sold anywhere. None are really fully charged and a trickle charge will never hurt the battery even if it is fully charged.

Battery terminals are the biggest source of problems when they aren't tight or if they have any sort of coating on them from the elements. Never assume when a terminal "looks" good that it is. It only takes a few minutes to remove and wire brush the terminals and cable ends to be sure.
Always remove the negative cable first and replace it last when doing any service on the battery or cables. This eliminates any source of a short circuit (sparks) from a wrench that may contact the frame or other parts while the other end is on the positive terminal.
Remember that around batteries there is hydrogen gas that is created when a battery is charging. If a spark occurs and the hydrogen gas is present at that time, have a nice trip!

NEVER use a car or similar vehicle to jump start a bike, the higher amperage can damage the electronics on a bike and that gets very costly.
Always slow charge a battery in any vehicle. Fast charging can warp plates from heat buildup in a battery which will short them out and render them useless. It's advisable to remove the battery cables when charging to eliminate the possibility of damage to the electronics, except when charging with a battery tender.

I hope this answers a few of the regular questions about batteries.