If you've done all the normal "vibe-mods" like bar ends and bar rubbers etc... it might pay to check the torque settings for the engine/frame mounts, exhaust flanges and exhaust mid mount points, if they're too tight it may cause issues as much as being too loose can do.
My 17 model did have some vibes when new and with increasing mileage it did get better...but it's now as smooth as a baby's bum....(not that I go around feeling baby's bottoms😉😉). I fitted a set Evotech barends, Arrow SS headers, loosened all my engine and frame attatchment/mount points and re-torqued all to the specs in the BMW manual...I even retorqued the handlebar yoke mounts and steering head bearings. It didn't make a huge difference but was definitely noticeable.
What we need to understand is that these engines are essentially a race engine which was designed for the S1000RR race weapons back in ~2010-ish....they're raw and very powerful for their size and weight...what BMW have done is essentially "fettle" the same engine to make it a little more user friendly for the R and XR....and TBH....I think they've done an awesome job of it. I have previously owned a Blackbird, it's engine was turbine smooth....but it's engine was also less powerful and nearly twice the weight of the S1000 series of engines, it also had twin balance shafts to get rid of the normal i4 tendency to vibrate ...something the S1000 engines have never had.
Sorry for the long ramble...😯
Smithy .