Some guys here are f@cking clueless;
You can manipulate dynos and if a LC made 113 hp after it got hilltopped you paid money for nothing !
On the same dyno my R1100S made 87 rwhp.
R1200S 109 rwhp
2016 R9T 102 rwhp
2017 R1200GS 117 rwhp
Shaftdrive on a boxer looses less power than a chain because the power is transmitted straight to the driveshaft without another 90 degree geardrive;less than 10% loss while a chain especially if worn or dry can loose 12% between clutch and rear wheel.
These are facts !
So BMW definitely would not go through all the hassle,added cost and complexity of new VVL or VVT heads to end up with 4 hp more !
140NM TORQUE is great and more than enough but I still hope we also see the same in hp at minimum which translates to 130 rwhp...

So maybe the dealer was right quoting 129hp at the rear wheel...

As a 1290 Superadventure has really 150 and not 160 at the crank at around 135 at the rear wheel.
BMW is always very conservative with hp numbers as the Japanese,italians and austrians advertise more than they actually have...