Tech Tip - Battery Life

When should I replace the battery in my bike?

I've known John since he purchased his Sportster new in 1998.  I haven't seen John in a while due to moves kids, pets and job changes.  So, it was a surprise to see him at the service counter on Monday evening.

It turns out John is looking to sell his bike.  And he needs a battery to get it running.  This time of year, we see a lot of people come in for a replacement battery, and looking at the date codes on the old batteries we get an idea of approximately how long a battery will last in each of the types of bikes (turns out it's usually between 3 and 4 years with good battery care.)

John didn't have his battery with him so I asked him how old his battery was.  Turns out he was replacing his original battery!  That's over eleven years of service out of his original battery.  That's an exceptional life for a battery on a Sportster.  John attributed the long battery life to several things:

• He always pulls the battery out of the bike during the winter and brings it inside the house
• He keeps the battery on a Battery Tender battery charger inside the house
• When he's installing the battery every spring, he uses a corrosion protectant on the terminals

John didn't mention this, but after working on his bike a few times, I know he also tightens the heck out of his battery terminals to be sure the bolts don't come loose.  When the bolts come loose, the connection will arc and build up corrosion on the terminals and cables.  This can make the bike difficult to start and even prevent charging, leading to shortened battery life or even being stranded with a bike that won't start.

While John was at the counter explaining his battery care tips, another rider was nearby and overheard our conversation.  He remarked "I replace the battery in my bike every two years.  I can't afford to be stranded if my battery decides to die on the way to The Roundup or a bike blessing."

So, there you have two extreme opposites of the battery spectrum. John, whose original battery lasted and amazing eleven-plus years, and Earl who replaces the battery in his Street Glide every two years for peace of mind.

Ride Safe.
Chris Hajer