Full disclosure: One of my motorcycle batteries is eight years old and going strong, but the one in my V-Rod is only 6, for now
Anyway, I made a video on the 7 things that determine a motorcycle battery's lifespan, and how to maximize that longevity. 4 of these impactors of battery life are totally within your control, the other 3, not so much, but they're good to know before spending any money on a new battery (especially given the V-Rod's battery is a bit more of a PITA to get at than most other bikes).
I talk about why the first filling/setup/charging of a new battery is actually really critical for the battery's performance and longevity, how your motorcycle riding type impacts your battery's longevity, and the importance of proper battery maintenance and storage.
And then there are the things outside of our control:
I explain how battery capacity, type, and manufacturer choice all make a difference. I'll also explain why I recommend high-quality brands like Yuasa and Antigravity, and caution people against buying from fly-by-night Amazon and eBay brands with no website/office/contact/support.
Basically, I work offline in the motorcycle biz, and created a pretty comprehensive guide to maximizing your motorcycle battery's lifespan, because it's probably the #1 cause of people needing to spend money unnecessarily on bikes for towing and service. Hopefully this can help some people save some money and not get stuck somewhere.
If I missed anything or got anything wrong, please let me know and I'll pin a comment under the video to help other riders!