this

I haven't tried it but I'm pretty sure that 17" of untracked is fresh snow is over the limit even for my Moonlander. Although If any bike could do it.... Honestly all I'd need is one set of tire tracks or a snowmobile track to follow and I'd be fine.

I got into about a foot of untracked powder last year on a weekend ride and it was a lot of work, but totally doable. (see pic) It wasn't the bike it was the engine (me) that was the problem.