Shimano 105 brakes not releasing reliably

[bryanska]

Hello,

I have an older Schwinn Tempo with original Shimano 105 brakes.

They look great, but don't always return to "the full spread" after I
release the brakes. As a result, I'm dragging the pads against the
wheel ever so slightly.

I can tell when I spin the wheel. It spins for a while, but comes to a
complete stop because of the brake eventually.

If I rotate the whole brake assembly, I can return the brakes to a
position that straddles the wheel and doesn't touch it.

Any advice? Do I need to replace any particular part?

[RonSonic]

On 26 May 2005 20:54:30 -0700, "bryanska" > wrote:

>Hello,
>
>I have an older Schwinn Tempo with original Shimano 105 brakes.
>
>They look great, but don't always return to "the full spread" after I
>release the brakes. As a result, I'm dragging the pads against the
>wheel ever so slightly.
>
>I can tell when I spin the wheel. It spins for a while, but comes to a
>complete stop because of the brake eventually.
>
>If I rotate the whole brake assembly, I can return the brakes to a
>position that straddles the wheel and doesn't touch it.
>
>Any advice? Do I need to replace any particular part?

It sound more as if they aren't centered, rather than a failure to release.

Here's the standard advice:

http://www.parktool.com/repair_help/FAQindex.shtml

These guys explain this stuff pretty well.

Ron

[[email protected]]

bryanska wrote:
<snip>
> They look great, but don't always return to "the full spread" after I
> release the brakes. As a result, I'm dragging the pads against the
> wheel ever so slightly.
<snip>

Onc pad rubbing, or both?
Does it rub once/a few times per rotation of the wheel, or is it a
continuous
drag?

> If I rotate the whole brake assembly, I can return the brakes to a
> position that straddles the wheel and doesn't touch it.
<snip>

(I'm asuming that these have one central pivot bolt running through
both caliper
arms, through the fork (at the front) or seat stay brige (at the back),
and are
fastened there with a nyloc nut or two nuts jammed against each other -
if not,
then not all of the points below apply)

If it's only one pad, ie the calliper is opening wide enough, but a bit
off center,
then you can realign it by loosening the nut behind the stay, holding
the calliper
at the correct position, and retightening the nut.

If it's opening centred, but not wide enough, and you can open it a bit
more by
hand,
1. look at lubing around the pivot bold that the various parts of the
caliper
rotate around. Be careful not to get lube on the rim, tyre or pads.
2. see if the caliper front nut (also on the pivot bolt) is
pinched up too tight and is preventing the caliper arms from
rotating/returning
freely. Adjust with caution, you don't want to allow tomuch
back-and-forth play
in the arms along the bolt - jerky and dangerous.
3. Look and see if the brake cable is binding or stiff in it's housing
- if
so lube/replace as appropriate.
If none of 1,2 or 3 help, you may be looking at worn/old components, or
bad
installation. I think we'd need more description to diagnose any
further.

HTH

bookieb

[bryanska]

> Onc pad rubbing, or both?
> Does it rub once/a few times per rotation of the wheel, or is it a
> continuous
> drag?

One pad, and it just barely touches the front wheel at one point in the
rotation. I just had the wheels trued, and it's a slight touch.

With the back wheel, the one pad touches all the way around.

> (I'm asuming that these have one central pivot bolt running through
> both caliper
> arms, through the fork (at the front) or seat stay brige (at the back),
> and are
> fastened there with a nyloc nut or two nuts jammed against each other -
> if not,
> then not all of the points below apply)

Yup - I since learned this early Shimano 105 is a single-pivot sidepull
caliper.


> If it's only one pad, ie the calliper is opening wide enough, but a bit
> off center,
> then you can realign it by loosening the nut behind the stay, holding
> the calliper
> at the correct position, and retightening the nut.

Thanks! I'm going to try this.

Do you think it's safe for me to take off the brakes, break them down,
clean, and reassemble? Or will I end up with a floor covered in little
ball bearings or something?

[RonSonic]

On 27 May 2005 07:11:16 -0700, "bryanska" > wrote:

>
>> Onc pad rubbing, or both?
>> Does it rub once/a few times per rotation of the wheel, or is it a
>> continuous
>> drag?
>
>One pad, and it just barely touches the front wheel at one point in the
>rotation. I just had the wheels trued, and it's a slight touch.
>
>With the back wheel, the one pad touches all the way around.
>
>> (I'm asuming that these have one central pivot bolt running through
>> both caliper
>> arms, through the fork (at the front) or seat stay brige (at the back),
>> and are
>> fastened there with a nyloc nut or two nuts jammed against each other -
>> if not,
>> then not all of the points below apply)
>
>Yup - I since learned this early Shimano 105 is a single-pivot sidepull
>caliper.
>
>
>> If it's only one pad, ie the calliper is opening wide enough, but a bit
>> off center,
>> then you can realign it by loosening the nut behind the stay, holding
>> the calliper
>> at the correct position, and retightening the nut.
>
>Thanks! I'm going to try this.
>
>Do you think it's safe for me to take off the brakes, break them down,
>clean, and reassemble? Or will I end up with a floor covered in little
>ball bearings or something?

Unless they're really nasty, I'd settle for a some solvent a paint brush and
then re-oil.

Ron

[Robert Perkins]

RonSonic wrote:
> On 27 May 2005 07:11:16 -0700, "bryanska" > wrote:
>
>
>>>Onc pad rubbing, or both?
>>>Does it rub once/a few times per rotation of the wheel, or is it a
>>>continuous
>>>drag?
>>
>>One pad, and it just barely touches the front wheel at one point in the
>>rotation. I just had the wheels trued, and it's a slight touch.
>>
>>With the back wheel, the one pad touches all the way around.
>>
>>
>
The centering mechanism for these brakes is done by tightening the
mounting bolt (the allen head or nut on the opposite side of the frame
from the fork) against the flat nut where the spring is attached the
brake (14mm wrench needed). Loosen the mounting bolt. The whole brake
is free to pivot.

Then, what I did was to take out all of the slack from the cable so the
brake pads are jammed up against the rim. The brake is centered in this
position, since it is gripping the rim.

Then, hold the flats of the 14mm spring-holding nut to keep it from
twisting as you tighten the allen bolt/regular bolt that attaches the
brake from the other side.

Then readjust your cable tension so you have 2-5mm of clearance.

Make sure the brake springs can move freely through the plastic holders
on the rear side of the caliper arms.

Tighten the brake body bolt (the one sticking out from the center of the
brake) against the hex bolt next to the 14mm spring-holding bolt. This
adjusts the tension between the brake caliper arms. Too tight, the arms
stick. Too loose, the arms wiggle in relation to each other.


I have these brakes and just overhauled them.
You may want to disassemble them. I cleaned mine in a parts cleaner,
then had to disassemble them to replace a stripped bolt, and there was
dirt that didn't get cleaned.

Good luck.
Rob

[bryanska]

Rob! You rule, dude. Thanks!

No ball bearings tumbling out when you disassembled? All non-escaping
parts?