So my 15 was too slow cranking to start yesterday (without a boost) after just a couple days off the tender... so I'm ordering a new battery. Not sure what I did wrong to only get 3 years (always used tender) but it's definitely not putting out enough umph anymore.
There are so many things that could contribute to batteries dying from faulty chargers, to bad/faulty regulators- Im not terribly surprised to see a 3 year replacement schedule.
I would suspect the battery tender. It could slowly cook the battery if it's not working correctly.
Very true. I wonder what brand the charger is. "Tender" is to charger what "Kleenex" is to tissue. Truth is, they are not all created equal. Battery Tender™ brand chargers (for lead acid) are really good quality. I wouldn't say the same thing about some of the other brands out there.
I personally use CTEK chargers on all of my lead acid and AGM stuff.
On thing that I have noticed with Multi's and other crossover/adventure bikes, is that owners tend to run accessories that exceed to charging systems capabilities. On most of these bikes, adding headed grips and maybe one other thing will often require more power than the stator can produce. So, you'll wind up riding with the bike often in a state of discharge.
Long story short, my experience is that a compromised charging system is often responsible for premature battery failure.