friend of mine did the same on a new bike (not a BMW). Decat, new exhaust, no tune.
5-6 months later its in the shop sounding like a bucket of rusty bolts in the back of a pickup truck.
You're gonna spend a lot on a new zorst, spend the extra and get a tune as well. Its either cry now ($$), laugh later, or laugh now and cry later ($$$$)
I see. Question: Would it be enough to get, say, a PCV and download the closest configuration map while skipping the dyno session? I am nowhere near a bike dyno shop. Thanks for the heads-up.