front brake noise

[bluehose2012]

hi, I recently had my front brake pads changed. the brake is working fine.

at times, especially after riding awhile, the front brake lever makes a noise that almost sounds like a duck quack. it doesn't do it every time-and if I let on and off the brake, the noise seems to go away.

I believe my mechanic did everything he was supposed to when changing the pads.

any thoughts? thanks in advance.

the bike is a 2006, with 12,500 miles.

[JohnC]

...the front brake lever makes a noise...

Where is the noise coming from? The lever or the brake?

[alantf]

the front brake lever makes a noise that almost sounds like a duck quack.

The only thing that springs to mind is, check the little plunger that the brake lever operates (in the fluid receptacle) to see if it's moving freely.

[bluehose2012]

I think it is the lever itself. I looked in the fluid receptacle, and moved the lever back and forth. it doesn't look like the plunger at the bottom of the receptacle is moving at all.

should I try and get the plunger moving or do I need a whole new fluid receptacle?

[raul10141964]

wd-40 on the lever shaft an the contact with the plunger

[alantf]

it doesn't look like the plunger at the bottom of the receptacle is moving at all.



Is the lever in contact with the plunger, all the time? It should be. Seems like the plunger is sticking, so try to get it moving, first, with WD40 etc. like raul lotsanumbers said.

[bluehose2012]

I looked at the brake lever where it goes into a rubber housing, below the fluid receptacle. It might be sticking there. I will try to lube it.

The thing at the bottom of the fluid receptacle can't be lubed. It's covered by the fluid.

I was also thinking I might need a new piston. It's $42 on bikebandit.com and my mechanic would have to change it. I will try lubing the rubber housing first.

[bluehose2012]

I looked at the brake lever where it goes into a rubber housing, below the fluid receptacle. It might be sticking there. I will try to lube it.

The thing at the bottom of the fluid receptacle can't be lubed. It's covered by the fluid.

I was also thinking I might need a new piston. It's $42 on bikebandit.com and my mechanic would have to change it. I will try lubing the rubber housing first.

[alantf]

The thing at the bottom of the fluid receptacle can't be lubed. It's covered by the fluid.



I was thinking more about the bit outside the receptacle. If the bit inside is covered by fluid, then it's being lubed by the fluid.

[JohnC]

There is a pivot bolt that the lever rotates on. It needs to be greased periodically. Also, there is a pivot where the brake pushrod attaches to the lever. It also needs to be greased. If you remove the bolt the lever will come off and the pushrod pivot can come apart too. First, remove the lock nut from the bolt then unscrew the bolt.

If the noise is actually inside the cylinder you'll need a rebuild kit. You cannot introduce just any lube in there. It has to be compatible with brake fluid, which is glycol based, not petroleum based.

[bluehose2012]

agree with John C. I didn't remove the brake lever, I just sprayed white lithium grease in and around the lever mechanism. I rode around, used the brake a lot, then re-sprayed, rode some more. the noise is gone. you do hear the mechanical noise of the pads being applied, but the quacking sound is gone.

if the problem recurs, I will remove the brake lever and grease as above.

of note, the brake fluid is really corrosive. I wiped the bit that got on the tank off immediately and on the cylinder. there is a bit of paint peeling on the edges of the cylinder (this has happened on my other bikes). luckily, the cylinder is black and black magical marker fixed the problem.

thanks guys. she's running great-new brakes, rear tire and oil change with synthetic oil! happy and safe riding to all!

[JohnC]

Not corrosive like acid, but it makes excellent paint remover!

[bluehose2012]

I'm going to ride a bit and see how it goes. I may remove the brake lever and get everything greased up. thanks for the simple fix.