That Gen II windshield mechanism has got to be one of the weirdest, rube-goldbergian contraptions I've ever seen.
Mine chattered annoyingly soon after purchase, and the dealer helpfully squirted some lube through the fairing notches, which helped for about a day.
I finally resorted to removing the front fairing (!!), cleaning off all that lube overspray, (iirc the dealer used lithium soap spray lube -- what a mess!)
I polished the tracks with autosol metal polish, put a very small amount of waterproof lube on them, (can't recall what I used, but anything non-sticky and waterproof should work ok), and carefully adjusted the cable tension*.
One of the rubber seals was detached about one third it's length, so I re-glued it. Note that it wasn't binding, because the mechanism chattered even with the front fairing removed. YMMV.
I used silicone lube on the rubber seals, made sure the mechanism slid up and down smoothly, and re-installed the front fairing.
It's been smooth and chatter-free ever since.
*If you adjust the cable tensioner, be aware that only a very small adjustment is needed. The tensioner mechanism is not the most robust, and all that is needed is sufficient tension so that all the guide wheels pulleys rotate smoothly.