I just picked up a 13 650l a couple weeks ago, before I did Dave's mod , uncorked and piped it, I noticed when it was warm/hot ( no idea to tell how hot no temp stick yet), the bike would puff white smoke with a hint of blue in the same way you mentioned. Not sure if it was oil burning off new parts inside the exhaust or what. Doesn't seem to do it now with Dave's mods however..... I also am going to "tinker" with the mixture screw and wanted to ask you.. When u drilled , you ended up drilling the tube kinda flush with the screw that is hidden under the cap? Sorry this post is kinda late I have been a reader for a while just never made a account.
Thanks Dave - ohio