Harley Davidson Electra Glide. Service manual (1959 to 1969) - page 3
FORKS
GENERAL
The Hydra-Glide fork is comprised of two sets of telescoping tubes that
work against springs, with an oil filled (hydraulic) dampening mechanism
to control the action. The unit is engineered to give long service with
a minimum of repair. Oil change is not necessary unless oil has been
contaminated or leakage has occurred.
DUO-GLIDE (NON-ADJUSTABLE). The non-adjust-able Duo-Glide fork, as
illustrated in Fig. 2F-3, is for use on a solo motorcycle. The fork
"trail'' (the distance, at ground level, from the fork stem axis to a
perpendicular through the wheel axle) is set and cannot be adjusted.
This fork may be recognized by the two hexagon head upper bracket bolts
(2, Fig. 2F-3) in the slider tube tops.
DUO-GLIDE (ADJUSTABLE). The adjustable Duo-Glide fork is for use on a
motorcycle which operates with and without a sidecar. It is essentially
the same as the non-adjustable fork except it has a two-position bracket
that allows the trail to be changed for best solo or sidecar-equipped
operation, also a steering damper adjusting mechanism which dampens the
steering head to suit conditions and rider preference. All other
adjustments and repairs are made exactly as on the non-adjustable fork.
This fork may be recognized by the reversible bracket bolt washers, bolt
and stem design (18, 19, 20, Fig. 2F-4) as described in "Adjusting Front
Fork Trail.”
SERVI-CAR (NON-ADJUSTABLE). The Servi-Car fork is a combination of the
above forks. It has greater trail than the non-adjustable Duo-Glide
fork, but is itself non-adjustable. The stem and bracket are the same as
the adjustable fork except for the bracket bolt washers. In appearance,
it is similar to the adjustable fork.
CHANGING OIL
DUO-GLIDE (NON-ADJUSTABLE). Remove upper bracket bolt (2, Fig. 2F-3) at
top of each fork tube.
DUO-GLIDE (ADJUSTABLE) AND SERVI-CAR. Remove fork cover side panels or
headlamp housing and fork filler screws (23, Fig. 2F-4).
ALL MODELS. Remove drain plug, Fig. 2F-3 at the outside bottom of each
slider tube with a 3/16 in. Allen wrench and drain. Draining speed will
be increased by gently flexing the fork as it empties. Replace drain
plugs and pour 6-1/2 oz. of Harley-Davidson Hydra-Glide Fork oil into
each tube, 7 oz. if fork has been disassembled and washed. Measure
amount very carefully. Flow of oil into tubes will be increased if fork
is worked up and down during filling operation. Replace upper bracket
bolts and tighten securely.
The fork filling device shown in Fig. 2F-1 will
hasten and simplify the filling operation. The unit consists of a
Neoprene (not rubber) stopper to fit the hole in the top of the fork, a
length of flexible tubing, a funnel and an appropriate size can,
soldered to the top of the funnel.
To make a filler can, drill a dozen 1/4 in. holes in the bottom of a one
quart tin can (2), near the outside edge. Shape the bottom of the can
with a light hammer so that it is dished upward to assure complete
draining of oil through the holes.
