Breakfast on the road with a bit of WiFi. So a few quick thoughts.
When I took her out yesterday none of the characteristics were right,
Disappointing for an "upgrade". Mine was taken care of by a tuner and was a dream straight out of the shop. It was a different bike, like a flying carpet and so much less dive from the RaceTech front. Couldn't believe it.
I know virtually nothing about sag and preload or rebound. I know when Igofar set up my 16 he set the rebound at 1.5 turns, asked my weight, #170, and turned the preload in 6 clicks. When I road it, the bumps were "together"( no rocking horse), the throttle did not cause the bike to rise or fall dramatically and through the curves it stayed firm and planted regardless of surface conditions. This was all on stock Honda springs.
Now...I went back to the top of your thread....it looks like you installed the beefier spring on a stock shock? Without RaceTech rebuilding/revalving the shock for you? That may be an issue as the stock valving may not be a good match for the 1300 lb spring. Maybe somebody else went this route and might be able to help here with settings.
If Larry set you up with 6 clicks on the 900 lb spring, you should most likely start with less than that with the 1300 lb.
But there are other factors....
Is the RaceTech Spring the same length as the OEM?
Is the installed length on the shock (compressed length of the spring) same as OEM?
This will affect your starting preload and how much you should click in.
There is always the Poor Man's approach.
Main thing you want from the suspension is not bottoming out.
So you can start with no preload at all. Then crank in the rebound to match, based on driving tests. First crank it in just enough so the rear doesn't po-go stick anymore. Then keep going until you can feel it is starting to pack over bumps, and back it off a bit from there (take good notes of settings).
Ride it like that for a while, to see if you ever bottom out. If you do, start preloading more, step by step. Everytime you crank the preload, you'll have to tighten rebound a bit, again, until it packs, then back off a bit. Keep going with more preload/rebound until you don't bottom down anymore.
But you may find out that for best results, it may be best to have RaceTech rebuild/revalve the shock (if not done yet).