From Tokyo to Osaka with luggage?

So I'm going to Tokyo next year during summer with three friends for three weeks. I was thinking about going to Osaka after that for an extra week on my own (I have a friend I want to visit there), but I was wondering what the best way would be to travel from Tokyo to Osaka. I've thought about going by highway bus but the problem is that I'll be carrying two suitcases of luggage, and there isn't always room for that on buses. So what public transport would be best for me?

Thank you very much!

The question is do you really need 2 suitcases? Summer in Tokyo and Osaka is very hot. Best to travel as light as possible. Most public transportation in Japan involves stairs and or escalators. And a lot of people.. Flying is quick but maybe Shinkansen is a good Japanese experience? both similar cost now. Forget the highway bus.

Probably it's easiest to take the Shinkansen train, and forward your luggage (if the suitcases are really large) by "takuhaibin" next-day delivery service.

I travel regularly with one 26 inches suitcase on wheels. Many hotels have laundry or they can tell you where the nearest laundromat is. 2 suitcases for one person is sheer madness.

If you plan to fly out of Tokyo and you can do the roundtrip to Osaka within 7 days, consider getting the 7 day JR railpass, it is about the same price and you can use it if you wish to do some day trips from Osaka to Nara, Kyoto, Himeji, etc.

You could also save money by leaving Japan via Kansai airport and just getting a one way train ticket.

I would also agree with Auntie Bert, take just one suitcase and make use of coin laundries or hotel facilities.

Well, I wasn't trying to put the suitcase thing up for discussion, but I'm either going to take two small suitcases or one big one. I'll also probably be doing a little shopping in Tokyo so I need to take those things with me too.
Either way, even with one suitcase it seemed problematic to me. But thanks for all your answers, it does help a lot!

I have once read on one of the forums of the website, that it's also possible use a luggage delivery service. This service will pick up your luggage at your hotel in Tokyo and deliver it at your hotel in Osaka

You can take the shinkansen with luggage pretty easily. You might want to get reserved seating though so you don't have to lug your suitcase around. Or get stuck standing up for a hour or so.

I strongly agree with everyone else to travel as light as possible. It is near unbearable with the heat and humidity and toting around two suitcases is going to practically kill you.