If you don't know, snowmobile rear suspension systems (called a skid) are a self-contained unit with a front shock with a coil-over that absorbs energy as the front of the track impacts a bump. Typically, it is coupled to the rear shock and they work in tandem to disburse the energy throughout the skid. Towards the rear of the skid, torsion springs are used as the primary suspension of weight of the sled, rider, gear; the rear shock is often naked, has 10-15" of travel, and does a majority of the work.

With that context out of the way...

...Adjusting the torsion springs up on a sled is the best way to increase ride quality. It makes the ride firmer, but allows for more bump compliance especially at higher speed on rutted up trails as the shock can do that work while the springs manage the sled's free weight.

I have never messed with the preload on a motorcycle until last week.

With the new, firm Corbin seat, ride quality on the Honda was subpar. Teeth chattering at some points! I have read on this forum that the Gold Wings are severely undersprung, and to crank up the preload out back to make the ride softer.

This is opposite of the snowmobile - yes, increased spring pressure enhances ride quality on a sled - but it does not make it softer, it makes it more controlled.

So, I followed the advice on here and cranked up the rear preload using the knob to about halfway between soft and hard. It was at soft, as set upon delivery.

What a difference! The rear shock actually absorbs bumps pretty well; I can push down on the back of the bike and it compresses easily. I am pleasantly surprised, at not really sure why the two types of vehicles result in such different outcomes from the same adjustment.