Back of a Bus

Mark Thompson said:

I'm getting fed up with my brakes, they need adjusting every week.

In what way?

Quoted message said:

I have 'normal' brakes on the bike. The front one's a dual pivot and the rear one's a normal
single pivot dooberry.

Good combo. Are you having trouble with both?

Quoted message said:

How often do you lot find you need to adjust your brakes?

Very seldom need any major adjustments. It's at least many hundred miles before brake blocks need
realigning or replacing or cable bolts get undone for any reason. However, I do frequently make
minor cable or centering adjustments which take a few seconds whenever I feel like it just to get
brakes perfect for the sake of it. They don't /need/ to be perfect, though.

Quoted message said:

Do I just have stretchy brake cables?

Cables aren't normally stretchy, really. Replace cables if they're frayed or excessively squashed at
the fixing point or there's anything suspect at the lever end.

Are brake blocks wearing rapidly? Doing a lot of cycling in the rain? Maybe you could do with better
brake blocks (eg. Kool Stop Salmon).

~PB

Mark Thompson said:

I'm getting fed up with my brakes, they need adjusting every week. I have 'normal' brakes on the
bike. The front one's a dual pivot and the rear one's a normal single pivot dooberry. How often do
you lot find you need to adjust your brakes?

About twice a year at most for each bike. I what way do you need to adjust yours ? Are you blocks
wearing down really fast ? get some better ones. Perhaps you cables are slipping in the clamps. New
cables are cheap (£2.50 each for Clarks at Halfords).

Quoted message said:

Quoted message said:

I'm getting fed up with my brakes, they need adjusting every week.

In what way?

The 'feel' of the levers gets a bit squishy and there's more travel on them, and I don't stop as
fast. The difference is very noticeable. I keep having to pull the cable tighter.

Quoted message said:

Quoted message said:

I have 'normal' brakes on the bike. The front one's a dual pivot and the rear one's a normal
single pivot dooberry.

Good combo. Are you having trouble with both?

Yes. It's mainly the front one that I'm bothered about as that seems to be where most of my breaking
is. When I emergency break I usually get a small skid from the rear wheel so I'm happy with that,
but then I have to pull the cable tighter.

Quoted message said:

Quoted message said:

How often do you lot find you need to adjust your brakes?

Very seldom need any major adjustments. It's at least many hundred miles before brake blocks need
realigning or replacing or cable bolts get undone for any reason. However, I do frequently make
minor cable or centering adjustments which take a few seconds whenever I feel like it just to get
brakes perfect for the sake of it. They don't /need/ to be perfect, though.

Quoted message said:

Do I just have stretchy brake cables?

Cables aren't normally stretchy, really. Replace cables if they're frayed or excessively squashed
at the fixing point or there's anything suspect at the lever end.

The cable's only slightly squished at the fixing point (I'm guessing that's where it attached to the
break levers).

Quoted message said:

Are brake blocks wearing rapidly? Doing a lot of cycling in the rain? Maybe you could do with
better brake blocks (eg. Kool Stop Salmon).

I live in Manchester so yes, there's a little bit of rain :-) The rear ones should be dead soon so
I'll swap 'em over and ask at the bike shop for some nice ones.

Quoted message said:

About twice a year at most for each bike. I what way do you need to adjust yours ?

Pulling the cable further through the nut on the brake to tighten it up.

Quoted message said:

Are you blocks wearing down really fast ? get some better ones. Perhaps you cables are slipping in
the clamps. New cables are cheap (£2.50 each for Clarks at Halfords).

No sign of the cables slipping. I'll pay closer attention to this to see if it's happening. Are all
cables alike? I do like cheap, but prefer not hitting things!

Thanks for your help,

Mark

Mark Thompson said:

I'm getting fed up with my brakes, they need adjusting every week. I have 'normal' brakes on the
bike. The front one's a dual pivot and the rear one's a normal single pivot dooberry. How often do
you lot find you need to adjust your brakes? Do I just have stretchy brake cables? Please help
before I disappear into the back of a bus!

Mark.

Cables stretch a lot when they are new. Try pre-stretching them (like a gear cable) by pulling the
levers as hard as you can and holding them there for a while. When you release the levers the brake
pads will usually be miles from the rim! Repeat until bored/the cable doesn't stretch much more.

Mark Thompson wrote:
. Are all cables alike? I do like cheap, but

Quoted message said:

prefer not hitting things!

In thinking more carefully the £2.50 was for Clarks gear cables, not brake. I would expect them to
be similarly priced for inners only. I expect thre are better, more expensive cables but Clarks seem
to work OK for me. You should probably replace both inner and outer to ensure they are matched
properly, this will of course increase the cost. My front brake on my tourer is a little spongey
compared to my racing bikes. The tourer has old Weinman centre pulls with a cable hanger attached to
the headset. This hanger flexes as I pull the brakes aas do the calipers themselves, though the
latter much less. I am looking out for a spare front dual pivot caliper to fit.

Mark Thompson' (change warm for hot) said:

I'm getting fed up with my brakes, they need adjusting every week. I have 'normal' brakes on the
bike. The front one's a dual pivot and the rear one's a normal single pivot dooberry. How often do
you lot find you need to adjust your brakes? Do I just have stretchy brake cables? Please help
before I disappear into the back of a bus!

Recommended service is to replace the hydraulic fluid once every four years. Oh, and pads when they
wear out, no idea how long that will be...

Seriously, though, on my road bike I find I need to adjust brakes exceedingly rarely. Mind you,
they're crude old single-pivot caliper type, and not very good.

--
[email hidden] (Simon Brooke) jasmine.org.uk~simonOpen ↗

Iraq war: it's time for regime change... ... go now, Tony, while you can still go
with dignity.

On Sun, 14 Dec 2003 16:42:21 +0000, Zog The Undeniable <[email hidden]>

Quoted message said:

Cables stretch a lot when they are new.

Are you sure about that? I've not had that problem. I find new yoke cables on my cantis take a while
to bed in, but the main brake cables have always seemed fine. Brake travel is quite big compared to
gear travel and involves some serious tension, slight stretching of the cable doesn't sound as if it
would make a lot of odds.

Guy
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On Sun, 14 Dec 2003 15:42:08 -0000, "Mark Thompson"

(change warm for hot) said:

The 'feel' of the levers gets a bit squishy and there's more travel on them, and I don't stop as
fast. The difference is very noticeable. I keep having to pull the cable tighter.

That sounds to me as if you have slipping cables. I have known the cables to slip in the clamp bolts
when they get old. I would be inclined to inspect the outers and replace the inners. Assuming that
it's not just fade due to wet and crud on the roads, but I think you've eliminated that.

Guy
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Mark Thompson said:

Quoted message said:

Quoted message said:

I'm getting fed up with my brakes, they need adjusting every week.

In what way?

The 'feel' of the levers gets a bit squishy and there's more travel on them, and I don't stop as
fast. The difference is very noticeable. I keep having to pull the cable tighter.

I suggest tightening the cable bolts a little further than you did before to try and make sure they
can't slip - but replace if cables don't look right (at either end) in any way (including anything
more than slight squashing). Maybe try a different brand of inner cable. Slightly thicker may suit
your brakes better. Also check outer cables are not damaged.

"Squishy" is difficult as there can be all kinds of causes for that. A certain amount of sponginess
is actually good (brake blocks compressing, etc) - better than feeling rock hard and unresponsive.

Might be worth studying the details at www.parktool.com/repair_help/FAQindex.shtml#brakes ...could
make you think of something you've been neglecting?

I recently improved an old dual pivot brake by readjusting the pivots to reduce fore & aft play
between the arms (as explained on the Park site). A fiddly and scary job but the stiffening improved
efficiency a lot. Same sort of thing can be done with single pivot calipers. This is not related to
need for cable readjustment, though.

Regarding "stretch": A cable in perfect condition does not stretch to any significant degree. A
newly fitted cable may seem to stretch as it beds in or if an unravelled bit of it stretches
(perhaps).

~PB

you know? said:

Zog The Undeniable said:

Cables stretch a lot when they are new.

Are you sure about that? I've not had that problem. I find new yoke cables on my cantis take a
while to bed in, but the main brake cables have always seemed fine. Brake travel is quite big
compared to gear travel and involves some serious tension, slight stretching of the cable doesn't
sound as if it would make a lot of odds.

I think it's a myth. Most bike mechanics believe it, however. If you buy a new bike from an LBS
they'll tell you to bring it back after 3 weeks as the brake and gear cables all stretch. If you try
to argue, "Well actually..." you'll meet with hoots of derision. However, inner cables these days
are pre-stretched and I believe any further stretching is negligible. What I think is more likely is
that the curves in the outer cables change shape slightly, and possibly the ends of the outers bed
into their housings a little.

--
Dave...

On Tue, 16 Dec 2003 00:26:42 +0000, Dave Kahn <[email hidden]>

Quoted message said:

What I think is more likely is that the curves in the outer cables change shape slightly, and
possibly the ends of the outers bed into their housings a little.

Entirely plausible.

Guy
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