jargey3000

hi all. having a problem with rear brake callipers. when I apply brakes, only the (left?) calliper pad engages. the right one does engage on first squeeze, but just stays there. I have a video to show it nicely but not sure how to load it? its a .mov file on my ipad. can i use that here? I guess its a simple fix, but I'm pretty clueless...🙁looking for some help?

alcjphil

There are several different types of brake callipers, they are not generic. This sort of question leaves people guessing about both your problem and the possible solution. The more details you provide as soon as possible the fewer wrong guesses you will see.
It would be a very long answer if I were to address all the possible solutions for this problem.

jargey3000

jargey3000

couldnt load the video, but hers 2 pics, before squizzing brake lever , & after.
right pad just stays "in"

does this help?
is there a way to attach an ipad video?

jargey3000

its an older, walmart or whatever, bike🙂

alcjphil

l have to say that that is a scary looking brake calliper. It was very low end quality when it was new, and it looks as if it has seldom seen any sort of maintenance. It needs a full service and lubrication, along with brake cable replacement. here is a method for centring brake pads for these brakes,: https://davesbikeblog.squarespace.com/blog/2020/1/20/three-bike-maintenance-hacks.htm
but your brakes are far too far gone for this method to work properly. The brakes(levers, cables, and callipers) need a full overhaul

jargey3000

everything you say is correct...lol

tFUnK

Looks like it's centered okay (hard to confirm without seeing the other side simultaneously). Given the condition of the bike new brake cable and housing might help although the brake caliper itself looks to be in rough shape. The return spring in the caliper itself might be faulty.

jargey3000

i didnt get much help from that link above.

i dont want to spend any money on the bikejust thought someone might lead me thru how or which parts to adjust?

Spaghetti Legs 

More than likely the brake is not centered properly. Maybe the bike got laid on it’s side and knocked it off kilter. Anyway, the center bolt can be loosened by an Allen key on the rear side of the brake (other side of the frame brake bridge in the picture. You can readjust the brake, re-center it and tighten the bolt down.

Heres a brake adjustment link

https://www.parktool.com/blog/repair...-brake-service

Bill Kapaun

Obviously one caliper is frozen in place.
Disassemble, clean & lube the center pivot parts.
Keep track of the parts in order they come off, although that shouldn't be difficult.
Then, it's trying to hit the sweet spot on how much to tighten the acorn nut.
IF you actually get them to function correctly, you won the lottery!

These brakes tend to be very flexy and if the wheel is a bit out of true, you have problems.
In order to keep the pads from rubbing, you have to have them too far apart to get hard braking before you bury the lever into the grip. The wheel has to be true to keep the pads close without rubbing.
I actually got into wheel truing because of these type brakes. I flipped bikes, and I simply needed all the help I could get to makes these brakes work well enough to have a semi clear conscience. Thinner grips sometimes helped.

jargey3000

thanks all. not sure i understand all the terms, instructions...but ill have a look at that link,
and, whats the acorn nut?

Bill Kapaun

How many nuts do you see on the entire brake caliper?
Center
Pivot
These words are in the dictionary.

jargey3000

i guess i see 5...2 up top, together...,1 holding the cable, and 1 on each pad.

jargey3000

moderators(or anyone):
I'm trying to post a video of my brakes from my ipad but i get an error message:

Alert

Your file "IMG_2085.MOV" could not be uploaded. It is not an accepted file type.

is there a way to post the video on here?

dedhed

As previously mentioned cleaning and lubing the pivot as well as the cable.

Here is a good "how to" on centering side pull brake calipers.

Dave Moulton's Blog - Dave Moulton's Bike Blog - Centering side-pull brakes

LV2TNDM

The brake's position, and how much each arm pulls away from the rim, is determined by the center bolt and/or the spring mount on the center bolt. This is adjusted with either 10mm box wrenches, or an 11mm cone wrench, plus or minus. BUT proper adjustment requires proper set-up in the first place! Proper retraction also depends on the caliper arms being properly lubricated and adjusted. It's like a bearing in that it has an adjustable nut and a lock nut on the outside on the pivot bolt. Disassembly and lubrication of the caliper is definitely recommended. But this is not a simple repair, given all of the potential pitfalls. I'd suggest you scour YouTube for caliper brake videos. The more you watch, the more you'll understand and see all of the issues with proper brake adjustment.

Proper brake function also entails cable and housing functioning properly, as well as the brake lever itself. Plus, the brake pads have to be properly located for maximum braking, safety, and squeak avoidance.

And as pointed out, this is the lowest-quality rim caliper you're likely to encounter. No matter how much magic a top technician could do to this brake, it's still marginal. And since it appears you have chrome steel rims: once the rims get wet, they're suddenly even worse! Like deadly worse!!! (The bike wet probably can't meet the minimum requirements of the law - making a tire skid.) So please be aware.

dedhed

THe bottom up cable routing lets water in and collect to rust in the lower part of the loop as well

jargey3000

thanks for all the input folks!
yes, i realize this is an old clunker relic of a bike. just trying to get it in a more usable state, just to "go around the block" a few times!
I'll keep plugging away at it. thanks.