No electronic guru here although I do have a volt meter.
Innitially when I received the new battery from Purolator I installed it and put it on the tender for a couple days, proceeded to starting the bike and battery went dead, I figured the tender wasn't enough of a charge so put battery on regular car charger at 4 amp but now that its charged I want to use tender as a cushion when bike not out on the road.
I just installed new starter, 38 amp charging system, battery cables, starter and HD battery and want to make sure I will be trouble free this season.

I have a battery tender plus 12v I've been using for a couple years and was wandering how can I test it to see if its working upto par?

 

Why not just call them? 877-456-7901

 

Below ~12 volts, your battery is dead. Fully charged will be ~12.7+ (or whatever your manual says). Should show much higher w/ motor running/charging.

Use your voltmeter regularly to check the state of your battery; better to check this right at battery terminals, but check at same place each time. These routine checks will be made w/ the bike cold, not running, though it could be good to know what the voltage is at normal idle, and on increasing RPM's, so you can troubleshoot your electrical system if/whenever required; record this in your maintenance log. When leaving bike unattended for months at a time, record the voltage at regular intervals (weekly? bi-weekly? monthly? Voltage seems to drop faster w/ time and lower temps) so you understand how your battery discharges over time, w/ the bike just sitting, and just how long you can expect to go before needing to hookup a Tender.

After a few weeks of sitting w/o charging (5 weeks shouldn't harm a healthy electrical system), measure & record your battery voltage. Hookup charger. You should see a small rise in voltage, which should continue, over time, to slowly rise to a level higher than when you 1st measured it cold (w/ NO charger hooked up), and the Tender lights should indicate full charge. Note: this is only for the purpose of establishing baseline data; you can otherwise just leave the Tender connected, whenever the bike will be unattended for some time.

 

Good explanation lo-rider.

 

The battery tender presents such a low rate of charge that it may well take several days if your battery was completely dead. Seems as if I've seen a graph or something that says it will take a couple of days.

 

I have had 2 battery tenders go bad over time. The battery tenders are not that expensive (The Battery Tender Junior's) and I use mine whenever the bike will sit for more than a day. So what I do now is replace my tender when I buy a new battery. About every 4-5 years.

 

Thanks guys for the responses, but it really doesn't tell me how to test the tender to see if its putting out reliably.
I figured out how to check my battery for amount of amps are being drawn when ignition switch and when light switch is turned on using my voltmeter set to 10 amp and putting the leads to disconnected positive and battery positive post. Which by the way was .04 for ignition turned to on and 14 for switch set to lights.

 

I don't know about your tender, but mine has lights on it. Red for charging and green for charged. If yours doesn't have that, put your meter in series with the battery tender and monitor the current with your bike off. The current should drop off, the closer to a full charge that you get to ~ 13.8 volts.

 

You can lead a horse to water, but you can't make him drink.

 

I think many people go a little overboard when it comes to battery tenders.

If you have a good battery and your electrical system is in good working order, there is no reason to connect a tender to the bike every time the wheels stop turning....

I understand that some of the newer bikes have a constant draw on the battery due to the security system, but the bike should still be ok without a tender during the riding season, as long as it gets ridden once in a while.

My `89 Softail sits all winter without connecting to any type of battery charger. When I am ready to get the bike out of mothballs, I connect it to my charger, but it always gives me a green light which indicates a full charge. It fires right up. The battery is several years old, a westco AGM type.

One thing that constant use of a battery tender will do is hide a problem, like an above normal drain on the battery when the bike is not running, or a battery going bad that will lose charge over a short time.

I would rather have the battery run down while sitting in my garage than find out I have a problem down the road.

When installing a new battery, it is best to put it on a charger, not a tender.

I think 2 amp charge is what is recommended as max for a bike battery.