Board Thread:Boruto Discussions/@comment-3261234-20161118110518/@comment-9782468-20161128043848

TheKidXD wrote: Why isn't the Rasenshirken invisible. I'll wait... You guys can keep saying Kishimoto said this and that, but my point of view comes from him not contradicting himself left and right through the whole series. Rasenshuriken is a finished technique flying through the air, so it's still visible. It's still made of chakra.

Rasengans in general disperse when thrown (which is why you generally can't throw them). Boruto subconsiously added Wind Release to his, which meant that when he threw it, the chakra of the Rasengan dispersed but the actual wind had to go somewhere. So it went straight to the target. That's why the tech is invisible to Byakugan users; it's not made of chakra once it leaves his hand, it's just wind that hits with the force of a Rasengan.

That's how I view tha Vanishing Rasengan, anyways.