Rear Drum Brake bent?

[Shoshin]

Good morning everyone..

Green as grass to bikes, and to bike repair.

Keeping things simple, doing small tasks, recently changed my tubes and tyres on my 79 CB125s.

After reassembly(and a couple spare tubes!) the bike handled well for a few hours.

On my way home I applied the rear brake, and felt/heard a noise and it was easy to press without result.
Thought I'd dropped a piece, so stopped and went hunting. Found nothing, so reinspected the bike.

The bar that applies the rear brake was bent at over a 90° angle, and the shoe of the brake had rotated around to the top of the wheel. The bracket that the brake bar attaches to was bent open..

Can I rebend this bar straight, or is a replacement necessary? It looks like the bolt that held the brake in place dropped out and when the brake was applied, nothing stopped the drum from flipping around.

I bet it pretty straight, but it's not totally true.. as long as the bar is secure, will it not bend again?

Here's an imgur to help explain
http://imgur.com/tuKlsfO

 

[VonYinzer]

An actual picture would be more helpful.

That sketch makes it look like things are broken, and therefore need replacing. But I'm not really sure.

 

[carnivorous chicken]

Picture would help.

But it might not bend back if it was secured properly. Hell, it's only the brake. Roll the dice!

Just jokes. Replace it (and make sure it's secured properly).

 

[Rich Ard]

Your sketch makes it look like the brake actuating rod, which goes through the lever arm on the brake drum, is what bent - is that correct? If so, it needs to be replaced.


There should also be a flat bar, though, that holds your brake drum so it doesn't spin (a "brake stay"). Is that missing as well?

 

[carnivorous chicken]

Your sketch makes it look like the brake actuating rod, which goes through the lever arm on the brake drum, is what bent - is that correct? If so, it needs to be replaced.


There should also be a flat bar, though, that holds your brake drum so it doesn't spin (a "brake stay"). Is that missing as well?

I wasn't sure which either, but if it's the stay and it bent, bending it back and running it doesn't mean it won't just bend in the same place when there's pressure from braking on it. and if it's the rod, those things can be pretty fragile in my experience (especially when it comes to removing rusty ones, which tend to snap).

 

[Shoshin]

Definitely not broken. The sprung brake bar is attached to the drum using a number of parts, but the flange that holds them just spread and released the end of the bar. I've re-bent it and will be reattaching the wheel shortly, but will be fabricating a new part this week (I love having a metalworker as a friend!)

Where's a good place to get parts like these for older bikes?

Sorry about the lack of photo. I found you guys late at night while browsing and wanted to post before morning

 

[Flugtechnik]

It kind of sounds like you are missing the brake stay, or else the arm wouldn't have been able to rotate up like that. If you don't have a brake stay, the stuff will just break again. Pics would be most helpful.

 

[Rich Ard]

Re: Re: Rear Drum Brake bent?

Definitely not broken. The sprung brake bar is attached to the drum using a number of parts, but the flange that holds them just spread and released the end of the bar. I've re-bent it and will be reattaching the wheel shortly, but will be fabricating a new part this week (I love having a metalworker as a friend!)

Where's a good place to get parts like these for older bikes?

Sorry about the lack of photo. I found you guys late at night while browsing and wanted to post before morning

You gotta post pics - the lever on the brake drum is cast aluminium and should break before it bends much.