The battery in your Honda Ruckus is just beneath the rear battery box cover. Remove 4 screws that look like these two and pull the cover off. The battery is on the right side and is held in place by the single bolt at the top of the metal strap.

Can you recharge the Ruckus battery?
Yes. The original battery is a YUASA, but most replacements are also factory sealed and service free.
Can I jump a Honda Ruckus with my car?
Yes, and you shouldn’t need to start your car in order to do so.
What kind of charger do I need to recharge the battery?
A 12 volt trickle charge (or slow charge) will work fine. Read my Battery Charging Tips page.
What type of battery is in the Honda Ruckus and Zoomer?
The original equipment is a Yuasa YTZ7S 12 volt battery, a factory sealed and activated motorcycle battery. A different brand may give an equivalent battery a part number that ends in TZ7S, such as BTZ7S.
Where can a replacement battery be purchased?
Buy a Ruckus battery here: Yuasa YUAM727ZS YTZ7S Battery