Hi All,  As Robbie correctly stated, at a Tempo of 80, eight feet
of paper should pass over the trackerbar in one minute.

Setting the airmotor governor, which controls the uniformity of
the speed of the airmotor irrespective of the vacuum level, so that
it conforms to industry standards is relatively easy.  A complete
explanation and test procedure is given at
http://www.player-care.com/governor.html

Basically, it involves the use of a standard test roll and a stop
watch. Adjustments are made at three basic tempos; zero, 10, and 70.

Unfortunately, a lot of factors come into play with regards to any
selected tempo being exactly what it should be.  However, if everything
in the system is in good-to-excellent working order, a tempo of 80 is
exactly the same on every make and model of player piano.

Musically,

John A Tuttle
Player-Care.com
Brick, NJ, USA