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date: Thu, 02 Oct 2008 13:55:59 +0100,
group: uk.rec.cycling
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Repairing disc brakes
Due to initial neglect and then extended procrastination the disc brakes
on my MTB are wrecked. Over last winter something happened
(freeze-thaw?) causing the brake fluid to ooze out at both ends of the
lines and gelify or gunkify.
I now want to repair this after doing nothing about it for the whole of
the summer. I guess I will need to:
* throw away the brake lines (I assume cleaning them is pointless)
* clean the all the mechanisms
* attach new lines
* put in new fluid.
The brakes are Hayes (not sure of the model number.)
Top tips accepted on cleaning the mechanisms.
Do I need to buy Hayes' lines or are they generic?
Any recommendations for over-wintering the bike once fixed?
Colin
date: Thu, 02 Oct 2008 13:55:59 +0100
author: Colin Blackburn
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Re: Repairing disc brakes
On 02/10/2008 13:55, Colin Blackburn said,
> Due to initial neglect and then extended procrastination the disc brakes
> on my MTB are wrecked. Over last winter something happened
> (freeze-thaw?) causing the brake fluid to ooze out at both ends of the
> lines and gelify or gunkify.
Frankly, considering the importance of brakes, I would replace the lot.
Who knows what might have happened internally?
> Any recommendations for over-wintering the bike once fixed?
Keep riding :-)
--
Paul Boyd
http://www.paul-boyd.co.uk/
date: Thu, 02 Oct 2008 18:59:59 +0100
author: Paul Boyd
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Re: Repairing disc brakes
Paul Boyd wrote:
> On 02/10/2008 13:55, Colin Blackburn said,
>> Due to initial neglect and then extended procrastination the disc
>> brakes on my MTB are wrecked. Over last winter something happened
>> (freeze-thaw?) causing the brake fluid to ooze out at both ends of the
>> lines and gelify or gunkify.
>
> Frankly, considering the importance of brakes, I would replace the lot.
> Who knows what might have happened internally?
Yeah, I forgot that as an option, probably a lot less fuss too.
Do all brands mount the same way? (Two allen bolts IIRC).
Any recommendations?
>> Any recommendations for over-wintering the bike once fixed?
>
> Keep riding :-)
Unfortunately I don't do too much MTBing [1]. Just like it to be there
when I need it!
Colin
1. My attitude to trails, tracks and hills is that I'd rather run than
cycle. My attitude to roads is that I'd rather cycle than run.
date: Thu, 02 Oct 2008 19:29:31 +0100
author: Colin Blackburn
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Re: Repairing disc brakes
On 2 Oct, 19:29, Colin Blackburn wrote:
> Do all brands mount the same way? (Two allen bolts IIRC).
There's two basic types of mount, ISO and Post Mount. Both use 2 allen
bolts but the bolts go indifferent directions. You can get adapters.
> Any recommendations?
>
> >> Any recommendations for over-wintering the bike once fixed?
If the problem really was fluid freezing maybe you should consider
cable operated disks?
date: Fri, 3 Oct 2008 00:49:22 -0700 (PDT)
author: POHB
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Re: Repairing disc brakes
POHB wrote:
> On 2 Oct, 19:29, Colin Blackburn wrote:
>> Do all brands mount the same way? (Two allen bolts IIRC).
>
> There's two basic types of mount, ISO and Post Mount. Both use 2 allen
> bolts but the bolts go indifferent directions. You can get adapters.
Cheers.
>> Any recommendations?
>>
>>>> Any recommendations for over-wintering the bike once fixed?
>
> If the problem really was fluid freezing maybe you should consider
> cable operated disks?
That's certainly an option. I also wondered about the differences
between mineral oil and DOT systems in this respect. Though mechanical
might just be a hole lot easier.
Colin
date: Fri, 03 Oct 2008 09:29:00 +0100
author: Colin Blackburn
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Re: Repairing disc brakes
Colin Blackburn said the following on 02/10/2008 19:29:
> Yeah, I forgot that as an option, probably a lot less fuss too.
>
> Do all brands mount the same way? (Two allen bolts IIRC).
>
> Any recommendations?
I've only ever used Shimano, and have no reason to change so have no
experience of others. Go for LX upwards, as the pads are more widely
used within the Shimano range as well as offering the option of sintered
(metal) or organic pads. I much prefer the former. Shimano brakes are
post mount but come with adaptors for ISO mount so you're covered both
ways. I reckon it's about 99% certain that you have ISO fittings on
your bike. Just make sure you change the discs as well and get the
right adapters for the disc size. A handy hint if you happen to have a
180mm disc on the front is that a standard 160mm rear adaptor will work
for it rather than buy the "special" 180mm front adaptor.
Another advantage of Shimano brakes is that they use mineral oil rather
than DOT brake fluid so it's "nicer" to use and won't damage paint if
you spill any.
--
Paul Boyd
http://www.paul-boyd.co.uk/
date: Fri, 03 Oct 2008 10:13:05 +0100
author: Paul Boyd
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Re: Repairing disc brakes
On Fri, 03 Oct 2008, Colin Blackburn wrote:
> POHB wrote:
> >
> > If the problem really was fluid freezing maybe you should consider
> > cable operated disks?
>
> That's certainly an option. I also wondered about the differences
> between mineral oil and DOT systems in this respect. Though mechanical
> might just be a hole lot easier.
But cables can still freeze if they get any moisture in them - my
trice is particularly prone to one (cable operated disk) brake
freezing (the end of the cable faces upwards, the cable does a loop
with a definite low point).
I've always assumed hydraulics would be less prone to freezing.
regards, Ian SMith
--
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|o o|
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date: 03 Oct 2008 12:26:11 GMT
author: Ian Smith
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Re: Repairing disc brakes
Ian Smith wrote:
> On Fri, 03 Oct 2008, Colin Blackburn wrote:
>> POHB wrote:
>>> If the problem really was fluid freezing maybe you should consider
>>> cable operated disks?
>> That's certainly an option. I also wondered about the differences
>> between mineral oil and DOT systems in this respect. Though mechanical
>> might just be a hole lot easier.
>
> But cables can still freeze if they get any moisture in them - my
> trice is particularly prone to one (cable operated disk) brake
> freezing (the end of the cable faces upwards, the cable does a loop
> with a definite low point).
>
> I've always assumed hydraulics would be less prone to freezing.
I've never experienced cable systems freezing on my other bikes, all
stored in the same place as my MTB. But, if cable system freeze and then
thaw they are not going to suffer the sort of permanent damage I seem to
have experienced. There may, of course, be some other factor involved.
Colin
date: Fri, 03 Oct 2008 13:30:29 +0100
author: Colin Blackburn
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Re: Repairing disc brakes
On Fri, 03 Oct 2008 13:30:29 +0100, Colin Blackburn wrote:
> Ian Smith wrote:
> > On Fri, 03 Oct 2008, Colin Blackburn wrote:
> >> POHB wrote:
> >>> If the problem really was fluid freezing maybe you should consider
> >>> cable operated disks?
> >> That's certainly an option. I also wondered about the differences
> >> between mineral oil and DOT systems in this respect. Though mechanical
> >> might just be a hole lot easier.
> >
> > But cables can still freeze if they get any moisture in them - my
> > trice is particularly prone to one (cable operated disk) brake
> > freezing (the end of the cable faces upwards, the cable does a loop
> > with a definite low point).
> >
> > I've always assumed hydraulics would be less prone to freezing.
>
> I've never experienced cable systems freezing on my other bikes, all
> stored in the same place as my MTB. But, if cable system freeze and then
> thaw they are not going to suffer the sort of permanent damage I seem to
> have experienced. There may, of course, be some other factor involved.
I agree that once they thaw everything's OK.
It's when hammering down the hill towards the right-hand bend and
squeezing on the left brake lever reveals it to be frozen solid that
the problem occurs. Plus, thawing a frozen brake cable is quite
time-consuming (especially when doing it before setting off to work in
the morning).
regards, Ian SMith
--
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date: 03 Oct 2008 12:44:31 GMT
author: Ian Smith
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Re: Repairing disc brakes
On 03 Oct 2008 12:26:11 GMT, Ian Smith wrote:
> On Fri, 03 Oct 2008, Colin Blackburn wrote:
>> POHB wrote:
>>>
>>> If the problem really was fluid freezing maybe you should consider
>>> cable operated disks?
>>
>> That's certainly an option. I also wondered about the differences
>> between mineral oil and DOT systems in this respect. Though mechanical
>> might just be a hole lot easier.
>
> But cables can still freeze if they get any moisture in them - my
> trice is particularly prone to one (cable operated disk) brake
> freezing (the end of the cable faces upwards, the cable does a loop
> with a definite low point).
>
Can you not arrange a break in the cover, with cable stops and either a
pulley (al la Sturmy-Archer) or something like the Simplex demultiplicator?
date: Fri, 03 Oct 2008 13:01:35 GMT
author: _
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Re: Repairing disc brakes
On Fri, 03 Oct 2008 10:13:05 +0100
Paul Boyd wrote:
> Another advantage of Shimano brakes is that they use mineral oil
> rather than DOT brake fluid so it's "nicer" to use and won't damage
> paint if you spill any.
>
Despite all the warnings about paint damage I've never experienced
this except in one car when I spilled some and didn't bother to clean
it up properly. If you wipe with a dry then a wet cloth shortly after
spilling the fluid it doesn't seem to cause any problems.
date: Fri, 3 Oct 2008 14:04:23 +0100
author: Rob Morley
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Re: Repairing disc brakes
"_" wrote in message
news:qhk1tnkarvdv$.aw9qagyokz4d.dlg@40tude.net...
> Can you not arrange a break in the cover, with cable stops and either a
> pulley (al la Sturmy-Archer) or something like the Simplex
> demultiplicator?
Sounds like something out of the old batman :-)
date: Fri, 3 Oct 2008 14:04:44 +0100
author: Clive George
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Re: Repairing disc brakes
"Rob Morley" wrote in message
news:20081003140423.39b55f16@bluemoon...
> On Fri, 03 Oct 2008 10:13:05 +0100
> Paul Boyd wrote:
>
>> Another advantage of Shimano brakes is that they use mineral oil
>> rather than DOT brake fluid so it's "nicer" to use and won't damage
>> paint if you spill any.
>>
> Despite all the warnings about paint damage I've never experienced
> this except in one car when I spilled some and didn't bother to clean
> it up properly. If you wipe with a dry then a wet cloth shortly after
> spilling the fluid it doesn't seem to cause any problems.
Ok, another advantage of magura/shimano mineral oil is that it isn't
hygroscopic so doesn't go off in the same way.
(and another advantage for me is that my car uses it :-) )
cheers,
clive
date: Fri, 3 Oct 2008 14:10:22 +0100
author: Clive George
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Re: Repairing disc brakes
On 03/10/2008 14:10, Clive George said,
> Ok, another advantage of magura/shimano mineral oil is that it isn't
> hygroscopic so doesn't go off in the same way.
Actually, that's probably the main advantage, now you come to mention it :-)
--
Paul Boyd
http://www.paul-boyd.co.uk/
date: Fri, 03 Oct 2008 16:19:40 +0100
author: Paul Boyd
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