Read more about When Will My Motorcycle Battery Die? at Motorcycle.com.It depends where the bike lives: Hot and cold climates are both harder on batteries than temperate climes, and bikes that get ridden regularly are easier on batteries than ones that sit for months – though a good battery tender with a float feature negates much of that. In fact, I was bragging about the Shorai lithium-iron battery in my bike not long ago, which must be seven years old now and has never seen a charger, when my friend Jim said big deal, the original equipment sealed AGM battery in his VFR lasted 9.5 years, and his 21-year old Ducati is only on its second battery. So, sealed batteries can last a long time especially if you’re OCD about maintenance.
According to several sources including BatteryStuff.com, though, your 12.3-volt reading means your battery may be on its way to Nirvana; a fully charged one should read 12.7 volts or above. Since you like to play with your voltmeter, there are instructions to “stress test” your battery at the same page, along with a lot of other battery tidbits that will let you know for certain if it’s time to replace.
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