Just to chime in again, the manual regarding the S1000 suspension is very poor. Sounds to me like the HP4 sag is awful too.
The S1000 manual states 10-15ml front and 20-25ml rear. This is poor for 2 reasons, firstly that stiff setting is okay for a smooth track but will break your back on roads and the manual only tells you to measure rider sag, BMW are ignoring free sag settings.
After a year of using BMW measurements I reverted to the tradition way of measuring sag correctly and have 30ml front with 5ml free sag and 30ml rear with 8ml free sag.
this website is abit retro now but I've found it helps explain in it simple terms to people who've never messed with suspension before.
http://www.gostar-racing.com/club/motorcycle_suspension_set-up.htm