Z Brake upgrade problem

[docrice]

Hey guys, I finally finished my full z brake upgrade (30mm fronts, z rears (w/ebrake!) and master cylinder) and its wonderful, except i have a small problem. When i start depressing the brakes with some force (moderate level, doesnt need to be a lot) then i get this kinda thudding from the front left side of the car that i can feel through the pedal....it pulses the same way a warped rotor does, but its a thudding instead. I cant honestly say if its coming from the front left brake setup or the master cylinder, although i am suspicious of the master cylinder. I went through and checked all bolts/nuts, its all fine. This problem never occured before, so i've pretty much ruled out suspension (although i did put on AGX's about a week before i started the brake upgrade, with no pulsing though). any ideas? i'm pretty stumped. thanks for the help.


Rice