Lift the fuel tank, see 2.9.1.
Keep the vehicle in vertical position, with the two wheels resting on the ground.
Make sure that the fluid level is included between the "MIN" and "MAX" marks, etched on the battery side.
If this is not the case:
Remove the battery, 7.2.1.
Remove battery plugs.
Warning! Top up the electrolyte using distilled water only. Do not fill above the "MAX" mark as the level increases during recharging.
Top up with distilled water.