haha .. front brake isnt the best either, back brake is only meant to be used to steady your self while braking at high speed, and then as a brake at 20 or under, mostly front brake is used
they all do it... just get worse over time as the pin that they slide on wears as they tend to go dry and rust if you dont grease/check it regular.. even just checking em everytime you replace pads (5k miles or so) isnt enough.. dont get this prob on the the 06-07 onwards cos they changed the rear caliper..
__________________
04' DT125RE 32k miles and counting / 89' DT125R 3RN1 Rebuilt + Supermoto'd. "Those who risk nothing, do nothing, achieve nothing, become nothing"