Belt Noise
Belt squeak/howling/noise - whatever you want to call it, is a common complaint among owners of the V2K. Various fixes have been tried by folks with widely varying degrees of success.
Several people have either gotten fed up with the noise and replaced their belts or had to replace them for other reasons and found that the noise has stopped. It seems that the S&S Gates belt is the favored replacement and being kevlar is "slicker" and so much quieter.
Best price seems to be from directharleyparts.com - The part number on their site is: 49-3635 (1 1/2 inch wide, 133 tooth)