Its not a choke but merely a fast idle lever. Cold start enrichment comes from the Motronic engine management computer without your intervention. Read Roger04RT's posts for a complete explaination of how the Motronic works to manage the boxer fueling.
If you haven't already, I would ride it carefully (brakes could be iffy) to operating temperature not exceeding 3000RPM. Then, check the oil on the center stand after the oil cooler drains back into the sump (~2-3 minutes).
Your UTUBE vid sounds OK if not a bit clakety but, as mentioned, the boxer engine can be noisy at cold start.
TB sync might help a bit.
Techron fuel additive is in order.
Watch for engine oil leaks. Sitting for long periods can cause seals to harden and leak a bit. Fresh oil of good quality has seal conditioners so, small leaks may subside if present.
Put some heat cycles into the engine to get it back to normal again (ride it to temperature 10-20 miles, park it and do it again).
I cannot tell from the photo is the brake lines are braided. If they are OE rubber, they will fail soon. Replace them to insure you don't have a catastrophic brake failure.