BRAKES 2012-2014
Try to not use synthetics pads or "sintered", but organic or semi sintered ones…sintered are better for very aggressive riding/braking, but mostly are noisy
Sand the pads (in the 2012 models keep the sintered pads. the brake pump is very weak)
Grease the back of the pads lightly with copper grease
Make sure the brake fluid is in good shape and the type/specs you need, if in doubt replace with fresh one (not form an already opened bottle)
Make sure you do not have the little brake fluid deposit over-filled (top), there has to be some empty space, or your bike will be lightly "braked" and your disk/pads will deteriorate prematurely...and you will get less range
Check caliper position
Check caliper springs if any
Check wheel,. Is it true?
Sand the disk, it could have lightly crystalized
Make sure all the bolts in the system (including wheel) are properly tightened
After all of this has been preformed and before riding clean everything exposed to dirt/grease with isopropyl alcohol
When riding again try to not brake very aggressively the firsts 20-30 miles
It is a question of time that Zero will add double front disk brakes in the road bikes range. Single disk is not recommended for the kind of speeds/overall weight the new models are reaching. This last statement is coming from an expert
Another advice is to remove/replace the rear brake spring. In the 2012-14 (Have not checked the 15-16 models) there is an over designed spring like the one you would use in a dirt bike…you do not need that for a road bike…actually there is a kind of spring inside the brake pump, so the external one is just to keep the foot-pedal without rattling.
Test the rear brake. Doesn't it brake better now?