Re: will my bike make it from dc to chicago
700+ miles isn't unreasonable in the least. Many of us have accrued much more on our bikes. The trick is to make sure the bike is reliable for a non-stop trek of that distance.
Heed the advice given above. Do some trial rides of a much shorter distance with the bike loaded as you're predicting it will be. You'll be able to weed out some of the bugs, if any, and you'll stand a better chance of not being stranded miles from home, possible in the middle of nowhere.
Good luck. It's an ambitious endeavor but if you succeed you'll be proud.
I wouldn't say which, chain or friction drive would be better, they're both good if done right.
Keep us informed of your preparations.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"