Slightly blue smoke.

So the bike starts up now, no hesitation.

But one exhaust pipe tends to have a little bluish smoke. It's not super obvious, but how much smoke shoudl I get anyway? It's definitely more out of one pipe than that other. But it's not always there either. Sometimes when I start it up it'll be there, sometimes not. And the same for revving it up and/or driving it.

What shoudl I check for to get it running cleaner?