Rear V-brakes not working properly

[Yousef37]

My rear V-brake isn't working properly, it feels loose and barely creates any friction when I pull on it. I tried adjusting the caliper and brake pad position but this didn't fix it. Here is a video showing the problem:
View: https://youtu.be/i9pf4nP9yjM

 

[iluvmybike]

It i sticking on nds - you need to centralise it - there are some small x head screws on each side of the brake arm which will move the mech left or right for this purpose. Do check that the pads are not worn down as well as it your video the mech arms seem to be very pulled in at the cable.

 

[palinurus]

Tighten the small x-head screw which adjusts spring tension on the left brake arm (viewing from rear of bike, the part of the screw visible will get shorter if you are going the right way). Tighten a little, then test- keep going until both brake arms are releasing about the same distance after applying brake. If this doesn't work reply here.

 

[Vantage]

There's a couple things that could be going wrong here, but start with cleaning the brakes. Take them off to do this including releasing the cable. Yours looks a bit manky which won't be helping matters. The cable and pivots need to be clean to do their jobs properly.
When you've done that, watch this video from about 2 mins in, paying attention to the 3 little holes.
Also check the plastic housing which covers the coiled part of the spring. If that's bent out of shape its usually bollixed and worth just buying new brakes. I've a suspicion that's the issue because the centering screw on the right arm appears to unscrewed quite a bit whereas the left arms screw is about halfway screwed in.

 

[AKHiker]

Take calipers off, clean + lube first. Small metal spoke in back shoudl go into same hole on both sides-generally the middle one. Then adjust centering as needed based on position of pads relative to the rim.

Seen a lot of brakes where people keep adjusting the tension screws to compensate for lack of grease and rust on the bosses.

Check cable is moving smoothly and replace if needed. Adjust cable tension and you should be good to go.