I would definitely second jib71’s advice about getting as much of your luggage forwarded to NRT as possible with the wonderful Takkyubin service.

Do bear in mind that the service isn’t overnight, especially not from Kyoto. Have a chat with the concierge at your hotel and ask when they think it’s best to send it on. I’d also advise you to get to the airport at least half an hour earlier than usual to give yourself time to locate the suitcase – it’s straightforward enough, but I find everything easier when I’m not stressed for time.

I tried to leave some luggage at Nippori station in a left luggage locker earlier this year. I failed to locate one. You won’t have any problems finding them at Ueno or Tokyo rail stations though. As dhammer53 suggests, you could leave the remainder of your luggage at either of these stations (I mention these as you can get to NRT easily from either of them) and collect them when you’re ready.

Do have a search through the Tokyo(JAPAN) forum – and do please post any further questions there. And you’re welcome to add a vote for the forum name change. Confusing as it is, isn’t it?