[MikeDee]

It happened on my rear brake today. The brake lever bottoms and the brakes barely engage (sometimes they don't). The pads are about worn out, but still have some lining left. The question is it the pads almost worn out or do the brakes need bleeding? The brake lever isn't spongy, which would indicate air in the system.

 

[wyrm]

if the pads are less than .5mm thick then they are done. Any less it will give you the symtoms that you are describing. Air in the hose is a spongy feel.

 

[XSL_WiLL]

Check the reach adjustment. 2.5mm allen key at the knuckle by the master cylinder. The reach tends to back itself off.

 

[MikeDee]

Check the reach adjustment. 2.5mm allen key at the knuckle by the master cylinder. The reach tends to back itself off.

Yes, I tried/checked that first, but it wasn't the problem.

 

[MikeDee]

if the pads are less than .5mm thick then they are done. Any less it will give you the symtoms that you are describing. Air in the hose is a spongy feel.

I put in new pads and that fixed the problem. This concerns me though, because the brake should engage even if the pads are worn down to the metal backing. The lining, even on a new pad, is not that thick. I still had lining left. I think this is a safety issue.

 

[XSL_WiLL]

When you squeeze it, is it generating enough pressure to lock the pads? If you hold it down, does it loose pressure?

It could be internal bypass in the master cylinder. Very common with those brakes.

If it's just squishy, try to bleed it first.

Oh... NVM... You fixed the issue with new pads.

 

[MikeDee]

I put in new pads and that fixed the problem. This concerns me though, because the brake should engage even if the pads are worn down to the metal backing. The lining, even on a new pad, is not that thick. I still had lining left. I think this is a safety issue.

Well, no it didn't fix the problem. I then bled the brakes, but that didn't solve the problem either. I called Hayes and they said the brake line was bad, something about an internal leak between the inner part of the line and the outer covering. He seemed pretty convinced that that was it, so I ordered a new brake line. I can find no external leaks in the system. I'll keep you posted if this solves the problem.

 

[MikeDee]

When you squeeze it, is it generating enough pressure to lock the pads? If you hold it down, does it loose pressure?

It could be internal bypass in the master cylinder. Very common with those brakes.

If it's just squishy, try to bleed it first.

Oh... NVM... You fixed the issue with new pads.

It turns out it was a bad bleed after all. Getting all the air out takes a bit of learning. I may also have a tiny leak somewhere that let fluid out/air in, but I can't see any signs of leakage.

 

[zaefod]

Yeah sometimes you have to adjust the angle of the MC while bleeding and even tap it with a wrench to loose the bubbles.