Hi all,

I’m volunteering at a refugee centre in Greece, where we rent out bikes to the refugees that live in the camp. One of the bikes has brake calipers that are totally misaligned, as shown in the picture.

Any ideas on the solution here?

Cheers,

Louis

Those brakes are below low-end. Those are brakes that dream of one day, god willing, maybe, maybe be mistaken for low-end.
There really isn’t much you can do with them. The metal is too soft. The reach is too big.
Bend them back into shape best as you can. Tighten the bolt on the rear side of the fork so that the part holding the double-ended spring doesn’t turn. Bend the spring until both sides retract enough to clear the rim.

Several things need to be addressed. First, find a nut to put on the pivot bolt (in addition to that already there). Then, adjust the pivot so that it moves easily without back and forth play. Lock the two nuts together they same as you would a cone and locknut. Next put an adjustable crescent wrench on the part of the caliper arms that hold the brake shoe and bend the brake arm so that the front of the shoe barely touches the rim first (toe-in). Now you can adjust the brake normally. If it's off center try tapping the spring where it loops on the side that is out too far, to rotate the caliper slightly.

need a 2nd nut on the front as a lock nut pair .

once that is resolved, center the brake with the nut on the other side of the fork, it fixes the whole thing to the fork

that should get the pad contact more equal . fine tuning the return springs can be done by bending them for more or less return force.


toe in on the right side done by bending the brake itself .. its steel so it will tolerate the bodging .



.....

On these kind of brakes, I just bend the spring on one side.

Is the spring even hooked to the caliper on the left side?

.
...as stated above, your best bet is bending. But that is one sorry assed bicycle shaped object you have to work with.

Given your situation, it might be worth a shot at contacting The Mike's Bikes Foundation. I know you're not in Africa, but many of your refugees have just come from there, so the foundation might be interested in designating you as a project.

It can't hurt to ask. Show them what you have to work with, and maybe give them a summary of how many people this could help.

A volunteer renting bikes to refugees. Nobody to do very basic maintenance.
I bet one of the refugees could fix it if you asked.

Thanks a lot for the swift and helpful replies guys! I’ll try locating a second nut for the front, and then giving it a good old bit of brute force. I really appreciate all of the advice!

Brilliant, I’ve taken a look at the Foundation and they look fantastic. I don’t think they’ll support the project we have going in Greece as it’s too small scale, and potentially only short-lived, but I’m going to look at volunteering with them in the future. Cheers!

Don't THINK.... FIND OUT.

and ask the refugees if any of them are good bike mechanics... you might be surprised.
When you have nothing, you learn to repair EVERYTHING.

I don't like the method of bending the springs to center brakes. Too much trial and error, and to easy for it to change back. The best method I have found for the type of sidepull shown is illustrated on the following video, starting at 9:18:

Here's what I'd do:
1) remove the arms by taking off the cable nut, and the center nut.
2) flatten both arms as best I could.
3) Reinstall the arms, but DO NOT USE THE EXTERNAL TOOTH LOCKWASHER AGAINST THE CALIPER ARM!
To explain, the arms must swivel independently, and if you have a toothed lockwasher coupling
to the nut, that arm can't pivot. You can use the toothed washer to give some spring, provided you
use a flat washer against the arms.
4) As others have said, you need an additional locknut on the end.

In summary, the brakes should be reassembled by putting the following on the spindle:
1) Any flat washer currently there
2) Caliper arm 1
3) A flat washer, if there is currently one there
4) Caliper arm 2
5) A flat washer
6) An externally toothed star washer
7) The current nut
8) An additional nut as a locknut

I'd use a small bit of nut locker ("LocTite" blue, or medium) on the locknut. Then I'd adjust the brake pads to meet the rim, then I'd reinstall the cable and tighten the cable nut. Then test.

As others have said, these brakes are about as low-cost as you can get. That said, they'll work better if they're adjusted properly.

Top advice, thanks! I managed to fix the brakes today based on your and everyone else’s suggestions. It seems that the second nut was key. I’m still not 100% on why though. Could someone explain how the two nuts work together to centre the brakes correctly?

It seems to me that the star washer should not be against the caliper. Is that bolt going all the way through the head tube? If so turn the bolt around and put the nut and star washer on the back.

Is there any manufacturer stamped on those brakes? Does the bolt appear to be original? If so it might have a long shoulder and the placement of the other washers and spacers will affect the operation of the caliper. If the bolt is just threaded all the way, it might suggest someone lost the original and you'll be lucky to get them to work right.

Any other bike like that with the same brakes that works correctly? If so, copy that assembly.

Its a common principal one nut is tightened agains the other and that vway neither will unscrew until one of them is loosened.
it occurs on the bearing adjustments A Lock Ring nut secures a adjustable Nut/bearing Race.

Again I recommend getting a Book on Bike Repair..(public Library in Town?) a really basic one

will get you some understanding of really basic mechanics .

star washer goes against the fork, behind the brake to keep whole thing from rotating so easily...

Merely locking the two nuts together does not center the brake. If it was centered after you locked them together it was merely coincidence.

I agree with this.

There are two main fastening points. We've been discussing fastening the arms to the brake frame. The brake frame has a spring that holds the calipers in a certain orientation. The other fastener holds the brake frame to the bike frame. To adjust centration on this type of brake, you snug that nut up a little bit - not too tight. You then use some leverage to push the spring I mentioned to center the brake. What we used to use in the bike shop was a screwdriver under the bike frame crossbar on the high side. You could push down on the spring and center the brake frame. Then tighten the nut. It turns out that your brake frame was in proper position, and once you straightened the calipers and reinstalled them, it was serendipitous that your calipers were set up correctly.