Just bought a 2005 bruin 4x4 350.
The rear brakes do not seem to grab right.
I had it back at the shop to have the plow installed, and they said they adgusted the rear brakes.
When I first took it out I had trouble stopping when backing down a bank.
I have tried to tighten the two wing nuts ot the end of the brake cable, but then I can not pull the handle in.
The front brakes will lock up the tires.

 

try bleeding them real good,,,my buddys 700 Sportsman's brakes wer'nt working right,,,we bled them real good,and they worked fine,,,,about two weeks later we found out how the air was getting in,when a line on his rear wheel broke

 

My brother in law has an 05 also, the rear brakes are just not that good, we just adjusted them so they don't drag and left it at that. Don't know what else to tell you there. Don't worry about bleeding them, they are drum brakes and just have a manual cable, no fluid to bleed!

 

I have an 04 Bruin, and when I apply the rear brakes all they do is drag. No matter how we adjust them they drag cause there is no weight back there. Just get used to applying a mixture of front and rear brakes.

 

Because of the way leading shoe drum brakes are designed, they are much more effictive in the forward direction and work poorly in reverse. This is one of the huge advantages of disk brakes, over drums.
Not much can be done, its just the design of them. They arent gonna work very well in reverse. If the drums are clean inside, no mud or dirt, and they have material on them, and they are adjusted right...then thats as good as theyll be..