In a message dated 97-02-20 16:11:40 EST, you write:
<< Is it as
simple as measuring the distance from the back of the wheel where it
mounts on the drum to the plane of the rear rim?
In a word, Yes. Actually that measurement is properly known as "Backset".
But is the more critical of the measurements as it is not affected by rim
width. Offset is really the measurement between the center of the wheel and
the hub mounting surface and can be a negative number ( ie. many front wheel
drive cars)
To measure simply lay a straightedge across the wheel at the bead seat (not
the flange of the rim) and measure to the flat surface of the wheel where it
contacts the drum/hub. If you still have the tire still on the rim, just
place the straightedge across the tire sidewalls, measure to the mounting
surface and then from the bottom of the straight edge to the rim bead seat
and subract the two.
I remember measureing mine (72 BGT) and I believe it was about 3 1/2". Check
me on that.
Rick Morrison
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