Jeffery, it's really a matter of personal preference. I weigh 185. I've tried mine at several different settings and have settled on 14 for most of my riding, one or two up. I've also set it at 9 or 10 in the past and that felt fine to me, one up. About the only time I increase it over 14 is when I'm pulling my trailer.
If getting on and off the bike is not a problem and you can comfortably touch the ground with both feet at a stop then why not pump it all the way up to 25. That is where mine is set at and it gives me maximum clearance when cornering.
Ya know, I've never had mine higher than 21, and that was with my trailer. Maybe I'll try it higher riding solo just to see. I'm not a speedster in the twisties so clearance isn't much of a concern for me.
When I first got the bike I was riding with the setting in the mid-point position (12½ ). However, I had trouble with the bottom of the bike scraping when I rode from the street up onto my driveway approach. I increased the setting to 25 and there was no more scraping. I didn't notice any other difference in riding or handling, so I've left it there.
The "Adjustor" is a simple Spring Pre Load adjustor and does nothing for dampening.
With that little factoid out of the way all you need to do is set it so that you have aprox 1" of upward rebound travel available which will allow 3" of downward compression travel.
I run 25 all the time - except when going long distances on super highways. I then set it at 5. At 5 the ride is softer more cushy for long rides. Used to set it at 10 but was constantly scraping the pegs hard - both the Kurys (on the vertical post) and the standards. I feel it is stiffer at 25 and like that.
Really depends on how aggressive you are. I have a 5 mile section of hilly twisty road on the way to work. I feel cheated if I don't scrape each morning - even at a setting of 25.
I weigh 245 lbs. 6 ft 3, in case you think i'm fat. I set my rear shock on 9 and it is very comfortable in town or on the road. I forgot to add that i have added the over/load wide load springs from progressive suspension front and rear. I never drag ANYTHING NOW. JD