V-brake pads make contact but don't apply pressure to wheel

Question

I own a hybrid Trek bike that uses V-brakes. When I apply the brake, the brake pads make contact with the wheel's rim, but don't apply enough pressure to actually brake the wheel. (No matter the level of pressure I apply, there isn't a substantial difference in the level of braking.) My immediate response was that the brake pads might be worn or too thin — so I installed a new pair. Unfortunately, the same problem persists.
I would appreciate any guidance on what might cause the problem. Do I need to find a better or thicker pair of brake pads? I apologize if this problem appears straight-forward; I am a newbie to both bike repair and the bicycle StackExchange community.
The question should be addressable based on the description above, but I have linked a very brief video here that demonstrates the problem.

Criggie · Accepted Answer

From your recording, it looks like the left side arm is the only one moving.  The right-side arm is not really moving at all when the lever is actuated.
I would adjust the small screw at the bottom of each V brake arm to equalise the tension of the retraction spring, so that both arms move away from the rim with about the same amount of force.
Adjust the barrel adjusters in the levers so they're 2/3 fully screwed in.  This allows some adjust in either direction without bottoming out or risking the lever falling out.
Then back off the cable's pinch bolt at the top of the left side arm, and pull some inner cable through, maybe 3~5mm.  Enough so both brake pads are barely clearing the rim.  Tighten the pinch bolt.
When you squeeze the brake lever, the pads should touch the rim well before the lever runs out of travel.  That's why you have minimal pressure on the rim.

Also check the housing is fully seated at both ends, and you may need to fiddle with barrel adjusters in the levers to get it dialled in.
This assumes your rims are running "true" with no side-to-side wobble.  You need to just-barely avoid brake rub when the brake is open.
You can do this - just take your time.  Do one brake completely and test it before you move onto the other brake.

Argenti Apparatus · Answer

If the force you are applying to the lever isn’t being transferred to the caliper so that the pads are not being pressed against the rim, there must be some flex in the cable housing.
Without more detail or pictures it’s not possible to determine exactly what the exact problem is. You can try tracing the cable from the lever to the caliper looking for issues.
You do not specific if the front, rear or both brakes are affected. If they both are there is a chance the bike was not built or adjusted properly. If you are not familiar with bike repair or maintenance having a local bike repair shop take a look may be a good idea.

Armand · Answer

I find it useful to narrow down which part(s) of the braking system are having issues.

It looks like you've got a partially-frayed cable with a strand sticking out just past the "noodle" tube, and a long tail past the clamp bolt. I'd trim off the strand and cut the tail to be maybe 1.5" long. Use a crimp cap, solder or even strong tape on the end to prevent it from fraying. Also, the flexible rubber "worm" between the noodle end and the clamp bolt should snap over the lip on the end of the noodle so it stays fixed relative to the noodle.

Can the brake arms stop the wheel? Just grab the tops of the two arms and squeeze using your hand. If that won't stop the wheel then the pads need to be adjusted to be closer in or there's something blocking the linkage from fully closing.

Another factor is whether the wheel is true or not. If not, the rim will "wobble" from side to side inside the brake pads when it is spinning and you won't be able to adjust the pads to be properly close to the rim.

If you've got issues re: 2 or 3 above, fix them by e.g. following the instructions at parktool.com

AA makes good points about the other end of the system.

V-brake pads make contact but don't apply pressure to wheel

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