I believe that it is to meet any governmental controls. 49 state - EPA = 126, California - CARB = 128 (added "smog controls" probably allows for the larger jet), the 130 was never a TW jet, I think it went in an XT. We use it often 'cause it works well. Other countries that get the 132.5 maybe don't have said restrictions, and/or are hotter where the added fuel helps with cooling?
Good questions, I'm curious to see what others say about it.
Did you get those 2015 bikes dialed in Rod? What did you end up with on your settings?