Royal Enfield SPRING FRAME O.H.V. 250cc CLIPPER 1954 Workshop Maintenance Manual page 47

ROYAL ENFIELD WORKSHOP MANUAL
Occasionally examine the terminals, clean
and coat them with petroleum jelly. Wipe away
all dirt and moisture from the top of the battery
and ensure that the connections are clean and
tight.
4. Servicing
If the battery is subjected to long periods
of night parking with the lights on, without
suitable opportunities for recharging, a low
state of charge is to be expected.
Measure the specific gravity of the acid of
each cell in turn with a hydrometer (see Fig. 3).
Section G4a Page 2
The following table shows the state of charge at
different values of specific gravities:
State of Charge
Battery fully
charged
Battery about half
charged
Battery fully
discharged
If the battery is discharged, it must be recharged,
either on the motor cycle by a period of daytime
running or from an external D.C. supply at the normal
recharge rate of 1.5 amp.
Temperature Temperature
under 90°F. over 90°F.
1.270 - 1.290 1.210 - 1.230
1.190 - 1.210 1.130 - 1.150
1.110 - 1.130 ' 1.1050 - 1.070