If you shock-discharge the battery when it only has a dry charge on it (starting load) you'll permanently cut out a good chunk of available capacity, id est the sulfur preloaded in the lead plates will never release into the electrolyte and the lead that those those sulphur ions are loaded into will never be made available to a charge/recharge cycle ... you're killing two birds with one stone to be sure.
Trickle charge the battery at 1/10 it's amp-hour rating for no less than 8 hours.
Trust me when I say I'm right, I used to sell these things and the guys that filled up their batteries and went right out for a ride were in the very next spring for a new battery. Additionally, If you're not getting 3+ years out of your battery YOU'RE doing something wrong, OR: your bike is overloaded with parasitic loads (likely add-ons or "upgrades"/your current generation device (alternator, generator, whathaveyou) is now rendered insufficient due to aforementioned "upgrades"/you wintered it in a state of less than full charge (neglected to top it off before storage)/you then neglected to charge it after 2 months of sitting for the winter/you added acid when you saw a low cell (put in WATER, you have sulphur locked in your plates and it will not release into a solution that's already full of sulfur)/your battery is too close to a heat-radiating source (oil bag, coil, who-knows)/lead sulfate (deeply affected discharge areas on the lead plate: sulfation) is sloughing off plates and collecting at the bottom of the cell (further reducing the electrolyte-to-plate surface area ratio) compounded by low-excursion vibrational shock from your improperly balanced crankshaft attributed to overboring and forgoing dynamic balancing and/or high-excursion vibrational shock attributed to your hardtail job/you overfilled the battery, thereby disallowing the electrolyte's ability to achieve optimum specific gravity at full charge/you're running a VRLA, SLA, AGM, gel-cel, or sealed battery (12.8-13.0VDC fully charged) on a charging system built for a flooded cell (12.6-12.7VDC) and it's NEVER achieving a full charge due to a charging voltage well below what's required and THAT leaves sulfur in the plates and allows it to sulfate and here again you're killing two birds with one stone by deleting usable plate surface area and recyclable sulfur ion/you're using a car battery charger set at 5 or more amps to fast-charge a depleted battery and boiling out the chemistry/you removed any heatshielding or cooling apparatus ... get how little this all has to do with the battery manufacturer now?
Persnickety sidenote: don't store your batteries on wood-over-concrete anymore (first off, they're made out of plastic cases nowadays; they won't leak like they did decades ago), throw them in the coldest room you can find after a full trickle and set them on styrofoam so they maintain a constant temp. from top to bottom.
Or, you know, spend the bucks on a new one every spring.
Agree with BigSky. Yuasa MF batteries come with instructions which must be followed to ensure long life and good performance.
This is taken from a good battery site:
Commissioning errors are aggravated by the fact that these batteries are delivered dry-charged with their own individual special acid cellular pack, the acid being of a higher concentration & density than standard battery acid.
This acid has to be allowed to trickle from its special pack into the battery slowly, to avoid trapping bubbles, then the battery has to stand while the acid is fully absorbed before being given a pre-delivery 30 minute charge. All of this takes a good hour, an irritating delay both for the impatient customer & the dealer trying to satisfy him while also attending to other things.
The inevitable tendency is to short-cut the correct procedures & this results in an under-par battery performance & an early warranty claim, usually at the expense of the motorcycle importer or distributor. Field studies by motorcycle manufacturers have shown that around half of all MF battery warranty claims arise from errors in commissioning procedure.
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