Porsche 911 GT3 R Technical Manual page 114

In addition one has to take care for sufficient axial play of the balance bar.
Thererfore a play of
0.9 ... 1.5 mm
between the plastic spacer and the fork end hast to be set. The
adjustment of the play is performed by altering the difference between the
two fork ends. This play is absolutely necessary to prevent a twisted
system. The lever ratios are not affected by this play.
feeler gauge
Furthermore, it is possible that the play changes when the balance bar
system is mounted on the car. Therefore, the play has to be re-checked
when the balance bar system is mounted on the car.
The pitch of the threaded balance bar rod is 1.2 i.e. when the fork end is
turned a full revolution the fork end moves 1.2 mm.
thread insert
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