The Battery Specifications For A Harley Flt

A line of Harley-Davidson Touring models stretches into the distance.

The classic Harley FLT was manufactured from 1980 to 1996, the ancestor of today’s touring motorcycles. This large-framed motorcycle had an 80- to 88-cubic-inch rubber-mount engine and a five-speed transmission. The battery installed at the factory was a sealed, 12-volt, lead acid unit, however, assorted models and sizes were used during specific production years.


The single 12-volt battery units installed in all FLT touring models should measure between 12.7 and 13.2 volts between terminals when fully charged. This voltage will only be reached if the motorcycle hasn’t been driven for two to three days. The lowest voltage in which the battery may still be useful while starting or driving is 11.8 volts.


Battery sizes can vary on differing FLT models, as can the amp/hour (AH) capacities (the rating system used for motorcycle batteries). For those FLTs built from 1980 to 1996, the AH rating should be 17, 20 or 21. Types of batteries that can be used are the wet flooded, or lead acid battery, and the absorbent glass mat, or sealed, maintenance-free battery.


No motorcycle battery lasts forever, but regular care can extend the battery’s life to the limit. According to, terminals and connectors should be kept clean, and the vent tube should be checked often for problems. If the FLT is stored for the winter, the battery should be removed and fully charged, or attached to a battery tender and kept in a cool, dry place. Always charge the battery according to service manual directions.