OK, FWIW, I installed the ZZR 1200 shock when the bike had Pilot GT's in GW sizes on it a few years ago, and did not notice any instability. Unfortunately those tires were discontinued, so I went to Avon's-110/80 and 150/80-Storm 2, Venom X. I don't recall noticing any problems with those tires. When they wore out, I replaced them with Storm 2, Azarro ST in the same sizes.
I did go to a GIVI windshield at about the same time-more upright, with the flip at the top only vertical-not past vertical like the stock shield is. I have since gone back to a stock windshield that I got used-the PO had drilled three 1 1/2" holes at the bottom I presume to reduce back pressure. I also have the Euro style fairing extenders on the bike and have for years. I weigh about 200# geared up and the bags and GIVI top box are packed full when I travel. (I tend to take a two-week, 5000 mile ride every spring and then ride the bike seldom the rest of the year-I have other bikes for local riding.)
If there is a way to measure sag w/o the help of another individual I would be on it. All I can say is the bike is much easier to get on the center stand with the ZZR shock, and there is just a little daylight under the rear tire with the bike on the center stand. I would suspect the ZZR shock raises the rear of the bike more than one might think.
Any ideas or suggestions would be appreciated. What preload setting would you recommend? TIA
