Single helmet preload should be fine. Funny thing with the ES, i do change the damping around quite a bit, but sometimes if i havent ridden it for a while i get on it and into the ride i think wow bikes seems great today. Check the settings and its on normal and on 0 damping. I think the base setting is quite good.
Am not saying that but it is a good place to start. Dont forget when you add luggage or another helmet etc it automatically ups the damping to suit. I go to hard when im going fast to keep it taught if that makes sense. Roads which are up down and all around etc.
Put up your location it makes it easier to formulate a reply.
Both fac191, and Bokerfork are both right. fac191 gave you a good starting point, and play around with the settings. Try soft, hard, +1 to -3. What you like, and what others like are likely to be a little different. I use 200lbs per helmet, and 50lbs for the luggage, which comes to the max of 450lbs.
I'm 300lbs, and ride rough roads. I'm using the same preload, but am using Hard 0. I think. I'll check tomorrow.
At 300lbs I'm assuming if you set it on -3 Soft you bottom out?
I have never bottomed this girl out, and I don't baby her. Even when my wife rides with me, I max the preload and adjust the rebound/dampening as the road(s) require. And she still handles fantastic through the curves. There's more than a few here that claim she's under sprung. I'm not one of them.
I tried 1 helmet, 1 helmet + luggage, 2 helmets, 2 helmets + luggage. Soft -3, STD and Hard, I pretty much went full circle hehe I'll see how it rides with my gf, on the Africa, it rode smoother 2 up.
