Follow up.  I now have clean, clean smelling belts--that
roll up just about as they did  before.

But I did realize that the driver side belt doesn't
roll up against the side of the housing as I thought.
It only does that when you have it apart and are
fiddling with it, er, observing its operation.

When put back together, the black cover provides an
aligning slot for the belt that should keep it centered.
Duh!

['87 Westy belts; others may differ, like my '81.]

Richard