for rear preload, it should be set so that you are at 1/3 the suspension travel with the load. this should put the bike geometry's at the design point.
If you set it too soft there is greater potential to get headshake,

because the fork angle is too low.
it also is not exact, I don't reset mine every time I change what I am carryiing.
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2009 BMW F800GS NON ABS

the best thing to buy for your bike is gas.....Neduro
Remote is not found on the coffee table.......seen on a T Shirt