Small Displacement Madness!

My bike lust has been focused on dual sports for quite some time but this winter a strange twist has developed.  Where I was once drooling over a KLR650 or DR650, I know find myself thinking about smaller bikes with less power.  I've always had a hankering for a DRZ400SM but I rode a TW200 once and it really made an impression.  Now, I find myself thinking about those big beautiful fat tires, big fuel mileage and little thumpy engine. 

Realistically, my riding will be 90% commute/fun and 10% long range.  The wee little TDub excels at city work and fun riding but long distance is not it's strong suit.  However, with a change in gearing it can run at acceptable US Highway speeds.  The tiny fuel tank can be swapped out for one from an XT350 which should yield about 180 miles before reserve.  The idea of minimal touring on such a small bike sounds good to me.  After all, there isn't anything to see on the interstate.