I know 2 x 9 is out there, but I know a single speed rider who ran 1 x 6 in a long demanding hilly event and it got me thinking....maybe a 2 x 6 would be a workable drivetrain that is lighter and simpler than 3 x 10, but has plenty of ratios to chose, including a decent granny bailout gear. There are classic disc brake compatible 6 speed hubs out there that a friend of mine pointed out, so I was thinking of trying to figure out a cassette and a pair of chainrings to use on a 2 x 6 drivetrain. Anybody try this on their XC MTB?