UPDATE TO ISSUE
Looks like I might have identified the problem = Oil Separator. It still seems as if power is lacking but the sudden loss of all power (like the rev limiter kicked in) is gone.
Replaced the entire assembly - all hoses etc. (ordered from Dealer). Here's are the part numbers:
1110180335 Oil Seperator $30
1110183182 Hose, VLRUN $28.50
1110181682 Hose $12
1110181882 Hose VLRUN $10
Took about 15 minutes