Reliant Rebel 700 1967 Workshop Manual page 17

To avoid the possibility of the wheel rotating on its axle between
setting the gauge and taking the reading apply the footbrake hard.
With the footbrake still applied, centre the bubbles in the level (E)
& (F) by turning the upper castor dial. Take the reading from the
dial and record. The castor angle should be 4°. If this reading is not
obtained, shims should be added or removed from the RH or LH
fulcrum fixing bolts.
Figure 7 Castor gauge
Figure 8 Steering template
Using template when turntables are not available
Place template against one of the front wheels and draw a line on
the ground parallel to the wheel. Then place the template on the
floor with its base along the line and draw lines P-Q and X-Y
(Figure 8).
Attach the clamp (Figure 6) and fit the Dunlop CG/5 gauge as
previously explained.
Steer the wheel 20° In as previously explained.
This can be checked using the template to see that the wheel is
parallel to the P-Q line (Figure 9).
Set castor dial to zero, centre the bubble (E) by turning the lower
knurled screw (H) (Figure 7).
Check the castor angle as previously explained and adjust if
necessary.
Figure 9 Steering template
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