Stromthusiast!
Join Date: Feb 2016
Location: Abbotsford, BC CANADA
Posts: 24
Since pre-load isn't supposed to change the spring rate of the shock but rather keep the shock within its "active range", you may simply have to 'trial and error' it. If the two of you sit on the bike and it hardly moves, soften things up. If, on the other hand, the two of you sit on the bike and it drops to the ground, leaving you with very little travel remaining, adjust the SR to bring the bike back up into its useable range. Of course, you also have to bear in mind that you are working within the limitations of the shock itself, and depending on how much the two of you weigh, you might find that you exceed those limitations... again, trial & error. Good luck, and congratulations on getting your wife on the back!
Arne Larsen
K5 DL1000 - Farkles: Adv Moto Bashplate, GIVI Engine Guards, MagStad, Cee-Bailey's Windshield, OEM Centerstand, OEM Gel Seat, Tank Bra, SW-MOTECH Chain Guard, Chain Oiler, HT SU Rack and Panniers
Previous Bikes: '98 Valkyrie Standard; '82 Aspy; '98 KLR650; '97 Valkyrie Tourer; '97 VT1100C; '82 KZ750E1