The stock DR350S uses a 6 Amp-hour lead acid battery. This capacity is required for electric start models (DR350SE), but not for kick start models. The dirt only (DR350) model does not require a battery.
Battery longevity Edit
Lead acid batteries lose the ability to hold a charge when discharged for too long due to sulfation, the crystallization of lead sulfate. They generate electricity through a double sulfate chemical reaction. Lead and Lead(IV) Oxide, which are the active materials on the battery's plates, react with sulfuric acid in the electrolyte to form lead sulfate. The lead sulfate first forms in a finely divided, amorphous state, and easily reverts to lead, lead oxide and sulfuric acid when the battery recharges. As batteries cycle through numerous discharge and charges, the lead sulfate slowly converts to a stable crystalline form that no longer dissolves on recharging. Thus, not all the lead is returned to the battery plates, and the amount of usable active material necessary for electricity generation declines over time.
Sulfation occurs in all lead-acid batteries during normal operation. It clogs the grids, impedes recharging and ultimately expands, cracking the plates and destroying the battery. In addition, the sulfate portion (of the lead sulfate) is not returned to the electrolyte as sulfuric acid. The large crystals physically block the electrolyte from entering the pores of the plates. Sulfation can be avoided if the battery is fully recharged immediately after a discharge cycle.
Sulfation also affects the charging cycle, resulting in longer charging times, less efficient and incomplete charging, and higher battery temperatures.
The process can often be at least partially prevented and/or reversed by a desulfation technique called pulse conditioning, in which short but powerful current surges are repeatedly sent through the damaged battery. Over time, this procedure tends to break down and dissolve the sulfate crystals, restoring some capacity.
Higher temperature speeds both desulfation and sulfation, although too much heat damages the battery by accelerating corrosion.
Smaller batteries Edit
A smaller capacity battery can be used on dual sport kick start models. Battery capacities as low as 1.3 Amp-hours are known to work well, although they cannot maintain lighting for more than 15 minutes if the engine is not running.
Battery elimination Edit
The battery can be eliminated entirely on dual sport kick start models. The battery can be replaced with a suitable capacitor. A capacitance of 10,000 μF or more with a voltage rating of 25 V or more is satisfactory. If a single large capacitor is not available, several smaller capacitors wire in parallel may be used. If a capacitor is used in place of a battery, all lights will go out when the engine stops. This might not be desirable when riding at night. Note that the bike will run without a battery or capacitor, but this might damage the electrical system, so it is strongly discouraged.