Looks like a Czar Freetrials, they came out in 2008.
Rear disc mount is IS +40, so with a 160mm caliper you'll use a 200mm rotor.
• Wheelbase: 1065mm
• Chainstays: 390mm
• BB Rise: +10
• Head Angle: 71°
• Seatpost: 27.2mm
I can attest to this. It took nearly 2 months for the lever he sent me to arrive, but Todge was good enough to send me another one at the 4week mark. When the original finally arrived I sent it back to him.
agreed, i used to think it would be fun to do this just to make people wonder how.. but it seems like a big hassle, plus having a deraileur and shifter adding weight to your bike, just to do one sort-of cool looking trick
ive been told you could also get this effect by running a geared bike with spacers on the casette, by tuning the deraileur so that one of your 'gears' would actually be a spacer
also maybe spend some time in the gym on days you dont ride surely the BEST way to ride better is to just keep practicing doing the moves properly, but it cant hurt to be in good overall shape