Disc brakes rubbing

Roger Zoul wrote:
This seems to be trickly. After fiddling

Quoted message said:

with it for several minutes before my ride, I got it so I wouldn't hear the
rubbing while going straight or simply rolling the wheel. I'd still get some
rubbing in turns, however.

I have zero exerience with disc brakes and suspect that this isn't so much a
'bent issue as a disc brake issue, but I thought I'd post anyway. I spent
some more time fiddling and I seem to be getting nowhere. It might help if
I could hold the bike perfectly vertical, but that seems impossible alone.

Comments welcome and appreciated

Roger, I suggest that you google for the disc brake manufacturer's site
and look up the manual. That will probably give you the proper
instructions for adjusting the pads so that they don't rub the rotor.

You should be able to get the front wheel into the dropouts without
much hassle. Stand in front of the bike and hold the stem with one
hand. Open the quick release. Take the tire in one hand holding it
lightly at the 12:00 position, and move it from side to side. Do this
with tiny movements. The axle should find the center of the dropouts
all by itself. Close the quick release. It will take some practice, but
if you find the balance point the bike will be vertical. It just takes
a bit of finesse.

When my disc brake was making a noise and slowing down the wheel on its own
I just loosened the cable screws like a rim brake. The screw is down by the
disc brake.

gotbent wrote:
:: Roger Zoul wrote:
:: This seems to be trickly. After fiddling
::: with it for several minutes before my ride, I got it so I wouldn't
::: hear the rubbing while going straight or simply rolling the wheel.
::: I'd still get some rubbing in turns, however.
:::
::: I have zero exerience with disc brakes and suspect that this isn't
::: so much a 'bent issue as a disc brake issue, but I thought I'd post
::: anyway. I spent some more time fiddling and I seem to be getting
::: nowhere. It might help if I could hold the bike perfectly
::: vertical, but that seems impossible alone.
:::
::: Comments welcome and appreciated
::
:: Roger, I suggest that you google for the disc brake manufacturer's
:: site and look up the manual. That will probably give you the proper
:: instructions for adjusting the pads so that they don't rub the rotor.
::
:: You should be able to get the front wheel into the dropouts without
:: much hassle. Stand in front of the bike and hold the stem with one
:: hand. Open the quick release. Take the tire in one hand holding it
:: lightly at the 12:00 position, and move it from side to side. Do this
:: with tiny movements. The axle should find the center of the dropouts
:: all by itself. Close the quick release. It will take some practice,
:: but if you find the balance point the bike will be vertical. It just
:: takes a bit of finesse.

Thanks, gobent. Actually, I can get the wheel in the dropouts with relative
ease...but there is just a slight amount of rubbing of the pads on the rotor
which bothers me. I took the bike back to the the LBS yesterday and the
owner adjusted the brakes and went through the procedure with me (I did
download the manual from the web as you suggested and read it carefully).
There probably was a little cable stretch involved that got adjusted out.
Still, even though the wheel turns more freely now, I can hear rubbing of
the rotor on the pads. Perhaps I'll just have to let friction do its thing.
I'm not set up with lights yet (working on that now) so I can't really do
any riding until this weekend to see how things really are.

nash wrote:
:: When my disc brake was making a noise and slowing down the wheel on
:: its own I just loosened the cable screws like a rim brake. The
:: screw is down by the disc brake.

Thanks. I might try that as I have just a little rubbing remaining after
LBS readjustment.

Roger Zoul said:

I was giving my Stratus XP its first shake down this morning, including the
carrier system the LBS owner worked out for me. I noticed that the only
problem I'm having in terms of loading/unloading the SXP at the moment is
getting the front wheel back on in such a way that the disc brake on the
front isn't rubbing on the pad. This seems to be trickly. After fiddling
with it for several minutes before my ride, I got it so I wouldn't hear the
rubbing while going straight or simply rolling the wheel. I'd still get some
rubbing in turns, however.

I have zero exerience with disc brakes and suspect that this isn't so much a
'bent issue as a disc brake issue, but I thought I'd post anyway. I spent
some more time fiddling and I seem to be getting nowhere. It might help if
I could hold the bike perfectly vertical, but that seems impossible alone.

Comments welcome and appreciated

I understand from my LBS (possibly with the emphasis on BS) that this
is an issue common to disc brakes. Apparently they can warp when too
hot (used too much/too intensely).

I just live with it. I try to loosen up the fit of the clamps, too, to
compensate for the warped disc. The LBS would fix it up, and after a
few potholes I'm back to hearing that whine of the disc rubbing against
its clamps (or whatever those things are called). So I loosen things
up, but that of course compromises my brakes. So I loosen it only up
to a point, basically where it's still rubbing but not so much that it
slows me down too much (I hope), with only the most minimally necessary
sacrifice in braking power -- luckily, with disc brakes, I still have a
lot of stopping power left.

It's only been my front 20" wheel (I have the HP Velop SMGTe) but
lately my rear 26" wheel has had very occasional issues with the brake
pad rubbing against its clamps. Oh well. Luckily things don't seem
too much changed.

"Prisoner at War" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Roger Zoul said:

I was giving my Stratus XP its first shake down this morning, including
the
carrier system the LBS owner worked out for me. I noticed that the only
problem I'm having in terms of loading/unloading the SXP at the moment is
getting the front wheel back on in such a way that the disc brake on the
front isn't rubbing on the pad. This seems to be trickly. After fiddling
with it for several minutes before my ride, I got it so I wouldn't hear
the
rubbing while going straight or simply rolling the wheel. I'd still get
some
rubbing in turns, however.

I have zero exerience with disc brakes and suspect that this isn't so
much a
'bent issue as a disc brake issue, but I thought I'd post anyway. I
spent
some more time fiddling and I seem to be getting nowhere. It might help
if
I could hold the bike perfectly vertical, but that seems impossible
alone.

Comments welcome and appreciated

I understand from my LBS (possibly with the emphasis on BS) that this
is an issue common to disc brakes. Apparently they can warp when too
hot (used too much/too intensely).

I just live with it. I try to loosen up the fit of the clamps, too, to
compensate for the warped disc. The LBS would fix it up, and after a
few potholes I'm back to hearing that whine of the disc rubbing against
its clamps (or whatever those things are called). So I loosen things
up, but that of course compromises my brakes. So I loosen it only up
to a point, basically where it's still rubbing but not so much that it
slows me down too much (I hope), with only the most minimally necessary
sacrifice in braking power -- luckily, with disc brakes, I still have a
lot of stopping power left.

It's only been my front 20" wheel (I have the HP Velop SMGTe) but
lately my rear 26" wheel has had very occasional issues with the brake
pad rubbing against its clamps. Oh well. Luckily things don't seem
too much changed.

I just noticed today for the first time when I put my disc bike in my old
bike rack that is not made for a bike with a disc brake down there. I put a
wedge underneath and made sure it was propped properly but you may not
notice that when you park at a store(the big racks are generally okay) or
someone may have kicked it who knows)
I understand the cables work the same as for rim brakes and if you put new
pads in you woul have to looses the cable anyway.

Cheers

This happens w/ great frequency on my brakes, which are on my upright
mountain bike. Great amounts of heat are generated in the braking
process and on long downhills, warping happens.
The rotors can be trued w/ a large adjustable wrench. Make sure that
the gripping surfaces of the wrench are very clean and I would clean
them w/ Acetone or denatured alcohol or something similar, so as not to
contaminate the rotor surfaces. Find the out of true sections of the
rotors and carefully bend them back to true with the jaws of the
wrench. A larger wrench -mine is 12" -will spread the pressure over a
larger area and not concentrate the bending forces so greatly. A larger
wrench might not work as well as it would cause interference w/ the rim
and or tires.
If you're a machinist or have access to a dial runout indicator, you
can find a way to check the trueness with one of those. I just do the
best I can w/ my eyes and ears.

Jim

nash said:

"Prisoner at War" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Roger Zoul said:

I was giving my Stratus XP its first shake down this morning, including
the
carrier system the LBS owner worked out for me. I noticed that the only
problem I'm having in terms of loading/unloading the SXP at the moment is
getting the front wheel back on in such a way that the disc brake on the
front isn't rubbing on the pad. This seems to be trickly. After fiddling
with it for several minutes before my ride, I got it so I wouldn't hear
the
rubbing while going straight or simply rolling the wheel. I'd still get
some
rubbing in turns, however.

Quoted message said:

Quoted message said:

It's only been my front 20" wheel (I have the HP Velop SMGTe) but
lately my rear 26" wheel has had very occasional issues with the brake
pad rubbing against its clamps. Oh well. Luckily things don't seem
too much changed.

Quoted message said:

Cheers

On 12/22/2006 15:05:45 'Prisoner at War said:

Disc brakes are just great. I have mechanical ones -- I can only wonder
how much more powerful the hydraulic ones are! I definitely reccommend
them. Full-suspension is another God-send. Bike riding is almost a
different activity altogether without those two recent additions to the
sport!

Quoted message said:

Now, if only HP Velo would make a light titanium version of the SMGTe....

Mechanical discs usually only push from one side so the disc becomes warped, it can be fine tuned by hand, hydraulics usually have dual pistons but the rotor still can warp, Hope have a solution to this with their floating rotors, these tend to stay true.

--

Buck

I would rather be out on my Catrike

http://www.catrike.co.uk

Floating rotors, eh? Hope, Inc., huh? Thanks for the ref! So my LBS
was right after all, about warping discs!

Buck said:

Mechanical discs usually only push from one side so the disc becomes warped, it can be fine tuned by hand, hydraulics usually have dual pistons but the rotor still can warp, Hope have a solution to this with their floating rotors, these tend to stay true.

--

Buck

I would rather be out on my Catrike

http://www.catrike.co.uk

"Prisoner at War" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Roger Zoul said:

I was giving my Stratus XP its first shake down this morning, including
the
carrier system the LBS owner worked out for me. I noticed that the only
problem I'm having in terms of loading/unloading the SXP at the moment is
getting the front wheel back on in such a way that the disc brake on the
front isn't rubbing on the pad. This seems to be trickly. After fiddling
with it for several minutes before my ride, I got it so I wouldn't hear
the
rubbing while going straight or simply rolling the wheel. I'd still get
some
rubbing in turns, however.

I have zero exerience with disc brakes and suspect that this isn't so
much a
'bent issue as a disc brake issue, but I thought I'd post anyway. I
spent
some more time fiddling and I seem to be getting nowhere. It might help
if
I could hold the bike perfectly vertical, but that seems impossible
alone.

Comments welcome and appreciated

Sorry...I thought this thread had died with little or no response...

Quoted message said:

I understand from my LBS (possibly with the emphasis on BS) that this
is an issue common to disc brakes. Apparently they can warp when too
hot (used too much/too intensely).

I did some googling and found a couple of sites which suggest that rotors
can easily be made true! I haven't tried it, but from the description it
seemed simple enough to do.

Quoted message said:

I just live with it.

that's why I'm doing for now. I still only have about 115 miles on the
bike.

I try to loosen up the fit of the clamps, too, to

Quoted message said:

compensate for the warped disc. The LBS would fix it up, and after a
few potholes I'm back to hearing that whine of the disc rubbing against
its clamps (or whatever those things are called). So I loosen things
up, but that of course compromises my brakes. So I loosen it only up
to a point, basically where it's still rubbing but not so much that it
slows me down too much (I hope), with only the most minimally necessary
sacrifice in braking power -- luckily, with disc brakes, I still have a
lot of stopping power left.

It's only been my front 20" wheel (I have the HP Velop SMGTe) but
lately my rear 26" wheel has had very occasional issues with the brake
pad rubbing against its clamps. Oh well. Luckily things don't seem
too much changed.

Nice bike. You might try googling for rubbing discs brakes to see if you can
find the site. I don't have it handy on this machine or I'd post a link for
you. I'm happy to have a partner in crime, though I do hope you get your
fixed. I don't like the notion of rubbing brakes while I'm riding.

Quoted message said: