I've really put the 790 through the wringer, conquering terrain that I've been unable to on my previous ADV bikes. The 790 ADV-R really is a game changer bike.
There are few stand out things that aren't quite where I'd like they to be though. The first is the bottom end torque. The 790 is rated at 94hp which is respectable but the power comes on at about 5000rpm... somewhere I rarely ride. This bike is a Ferrari, a thoroughbred and it really likes to rev. For the riding I do, I prefer a Turbo Diesel 1 ton truck to a sports car, not actually a Diesel of course but a bike with really good bottom end.
To get the 790 where I wanted it required a sprocket change to start. Simply dropping a single tooth on the front sprocket really made a noticeable change to the bottom end of the bike. 16T to a 15T, worth it!
The other thing I noticed right away was the clutch engagement was very digital; off/on. The friction zone is quite short and it makes riding in technical terrain harder than it really needs to be. Luckily, the 790 comes with a cable clutch so the clutch arm on the motor side is accessible and easily swapped.
I designed a new clutch arm that is 19mm (3/4") longer than the stock unit. This gives a better mechanical advantage (lighter clutch pull) and increases the friction zone by 60%(!). I also added a second hole half way better the original and the 19mm hole so you have 3 options to tune clutch engagement to your taste.
The Camel ADV One Finger Clutch: