My drivetrain is in need of some TLC (read part replacement) and I was wondering if it would be possible to swap out my existing rear system which consists of a Shimano 105 RD and cassette (12-25) with a MTB rear (say Shimano Deore w/12-34 cassette - 9 speed). For levers I have 105 integrated 10 speed brake/shifter system. The bike is the 07 Kona JtS. I want to keep the front as a double 46x36. Brief discussion with people indicate the challenge (possible show stopper) will be the compatibility between the brifters and new RD/cassette.
Appreciate any advice.