when I went to reno, I carried 1 of my bowling balls in a backpack (which was my carry on), and they had to open my bag and check the ball. ***NOTE*** When doing this, I would STRONGLY SUGGEST that you carry a ball without plug, as I had to go through a lot of BS since it was a ball that had plugwork.
Anyway, back to your original question, I wouldn't suggest carrying on the bottom piece (the part with the handle), as it won't meet the requirements of size for a carryon, which could then cost you dearly, since they would make you check the bag....whic would make you over the limit for checked bags, and I believe that you're looking at $100 US for 1 extra bag 1-way (and that isn't even for an overseas flight). Try checking the bottom part, and carry on the top or middle (though the middle probably won't have a decent carrying handle).
Big Willy Style
PS...can't wait to see ya next month!
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Just my $0.02 so take it for what the Foreign Exchange values it at! 
"I was raised by a cup of coffee..."
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