Compressionless brake housings for cable discs.

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reohn2
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Re: Compressionless brake housings for cable discs.

Postby reohn2 » 7 Aug 2018, 6:52pm

I have built three bikes with BB7's and one Circe tandem that I converted from V's to BB7 discs.
I've used ordinary brake outers on all of them,I have no braking problems whatsoever,indeed today I was braking with one finger from the drops to bring the bike from 35mph to 10mph PDQ.
I don't know what all the fuss is about TBH.
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TooManyBikes
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Re: Compressionless brake housings for cable discs.

Postby TooManyBikes » 7 Aug 2018, 7:18pm

Just been reading this review of a brand called Yokozuna which combines the longitudinal inner wire wrapped in a spiral outer wire, makes for a less 'bendy' cable though.

https://road.cc/content/review/229083-y ... ble-system

It hadn't occured to me that compressionless would be of use on rim braked bikes too! Doh.
My name is Michael, And I have too many bikes.

freeflow
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Re: Compressionless brake housings for cable discs.

Postby freeflow » 7 Aug 2018, 7:31pm

Yokohama cables are as common as rocking horse droppings. The extra long kit for jagwire compressionless housing is the way to go so you can have a continuous run from the brake to the caliper.

As ever getting a clean square cut is key.

I'd also like to mitigate the doom and gloom about TRP HY/RD brakes. They've been stopping me and my bike (120 kg +) since Jan 2015 without issues ( even one handed).

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foxyrider
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Re: Compressionless brake housings for cable discs.

Postby foxyrider » 7 Aug 2018, 8:03pm

freeflow wrote:
I'd also like to mitigate the doom and gloom about TRP HY/RD brakes. They've been stopping me and my bike (120 kg +) since Jan 2015 without issues ( even one handed).


Can you tell me how? Had mine for @ 4 years and they are a nightmare! You can set them up to work perfectly but 2 rides later you are stopping on a wing and a prayer! Every type of pad, different rotors, recablingg - same result, in fact the 180 disc on my front wheel needs replacing as it's worn silly (again).

I'd really like them to work, when they work they are excellent.

BTW I'm 82kg, the bike is @ 10.5kg and occasionally it carries up to 15kg of luggage.
Last edited by foxyrider on 7 Aug 2018, 9:36pm, edited 2 times in total.
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Brucey
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Re: Compressionless brake housings for cable discs.

Postby Brucey » 7 Aug 2018, 8:21pm

TooManyBikes wrote: Hadn't heard of that Giant gizmo before Brucey, interesting but pricey...

yes it has been out for a few years now (since 2013) and it seems to work OK but it is relatively rare.

...Is a bit of careful greasing of the mechanism while they are still new worth doing then as a preventative measure against corrosion?


with mechanical disc calipers a little fettling is not a bad thing to do. The problem is access , and what kind of grease to use. It can melt (when it gets hot) , migrate onto the pads and get turned into an abrasive slurry when dust from the pads gets into it.

cheers
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freeflow
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Re: Compressionless brake housings for cable discs.

Postby freeflow » 8 Aug 2018, 4:48pm

foxyrider wrote:
freeflow wrote:
I'd also like to mitigate the doom and gloom about TRP HY/RD brakes. They've been stopping me and my bike (120 kg +) since Jan 2015 without issues ( even one handed).


Can you tell me how? Had mine for @ 4 years and they are a nightmare! You can set them up to work perfectly but 2 rides later you are stopping on a wing and a prayer! Every type of pad, different rotors, recablingg - same result, in fact the 180 disc on my front wheel needs replacing as it's worn silly (again).

I'd really like them to work, when they work they are excellent.

BTW I'm 82kg, the bike is @ 10.5kg and occasionally it carries up to 15kg of luggage.


This has been discussed at length on this forum.

All other issues* being resolved, TRP HY/RD disk brakes are very sensitive to the position of the actuator arm when the brakes are off. You need to make sure that there is sufficient slack in the cable that the arm does not get pulled forward when you unscrew the locking nut. If this happens then the return port is always closed and you get exactly the behavior you are reporting.

So set up as follows

1. Unclamp cable
2. Screw in locking nut
3. pull cable finger tight
4. clamp cable
5. release locking nut. If there is any significant resistance to unscrewing the locking nut or the actuator arm moves forward when the locking nut is undone then restart at 1 but pull the cable with less force at 3.

6. When 5 has been achieved satisfactorily (no movement of the actuator arm but no excessive slack) then operate the brakes quite hard quite a few times to 'pump up' the system.

When set up like this my Hy/RD brakes work extremely well, only being affected by the amount of contamination of the disks.

The setup of the cable tightness is IMHO quite counterintuitive.

The travel of the levers will also be quite high, at least halfway before the brakes bite, but thereafter the modulation and stopping power is very good. The bite distance is greater for older style STI as the amount of cable pulled is not as great as more recent STI (e.g. 105 5700 series). If you are coming from full hydraulic brakes or tightly set up dual pivot brakes the amount of lever movement is disconcerting but is not incorrect. You just have to relearn how to brake.

Let us all know how you get on.

* all other things being equal

1. You are using decent compressionless housing
2. The housing has been cut square
3. The housing sits square in the ferrules (Achieving 2 does not automatically achieve 3)
4. The cables are adequately lubricated
5. The pads are not contaminated
6. The rotors have been bedded in correctly

TRM
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Re: Compressionless brake housings for cable discs.

Postby TRM » 10 Aug 2018, 5:47pm

Dunno if i'm too late and you've already made a decision but this year I fitted Jagwire Road Pro compression-less cables to my Genesis with dual pivot brakes and the difference was night and day. Much much more powerful braking and better modulation from the standard shimano cables that were previously fitted.

Cables where easy to cut square and file of any burs. They also come with a small section of wound steel cable to help bend around the handlebars as its more flexible than the compressionless outer.

TRM

gregoryoftours
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Re: Compressionless brake housings for cable discs.

Postby gregoryoftours » 11 Aug 2018, 11:15am

Cunobelin wrote:I run Avid BB7s on most of my bikes and trikes, an the runs are short, normally about 30-40 cms

I have simply used gear cable outers with no issues whatsoever


I've personally seen standard (not braid reinforced) gear cable housing fail catastrophically when used for brakes. It's especially vulnerable where any abrasion of the outer can take place, eg where cables cross or at the head tube. Brake outer being spiral wound obviously does not depend on the integrity of the plastic coating to hold the whole shebang together! Definitely not a good idea despite your experience with it.

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Mick F
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Re: Compressionless brake housings for cable discs.

Postby Mick F » 11 Aug 2018, 2:19pm

Cunobelin wrote: I have simply used gear cable outers with no issues whatsoever ................. Been my practice since the early 90's and never had a failure yet
This idea has never occurred to me, but it sounds a brilliant idea especially for the longer rear brake cables.

Not on Mercian as a "normal" road bike coz that's fine, but Moulton has a rather convoluted rear outer at the rear end of the cable run.
I've fiddled for ages with it trying to route it better, but a gear outer could very well improve matters as the rear brake feels spongey and vague as it is.

It's worth an experiment.
Mick F. Cornwall

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Mick F
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Re: Compressionless brake housings for cable discs.

Postby Mick F » 11 Aug 2018, 2:23pm

PS:
I wish I'd read this this morning.
It's been chucking it down since about 9.30am and since doing an hour of chainsawing soon after breakfast, I've been bored stiff all day.

I could have spent a happy hour or two fettling away. The day is still yet young, so there's time yet.
Mick F. Cornwall

Brucey
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Re: Compressionless brake housings for cable discs.

Postby Brucey » 11 Aug 2018, 2:45pm

gear outer for brakes is not at all a good idea. Some folk might get away with it (on many trikes you get short runs, small wheels= high brake torque, low cable tensions, "two front brakes" etc) but why the hell you would take the risk is utterly baffling. On normal bikes I'd describe it as 'borderline suicidal'.

If you want a good cable run that is also convoluted, think about using a combination of compressionless outer and V-pipes, or combined with short lengths of flexible spiral wound outer. Don't use gear outer; it is both stupid and pointless.

cheers
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iandusud
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Re: Compressionless brake housings for cable discs.

Postby iandusud » 11 Aug 2018, 3:05pm

I'm surprised that a brake cable will fit gear cable housing that is designed for a thinner cable.

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Mick F
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Re: Compressionless brake housings for cable discs.

Postby Mick F » 11 Aug 2018, 3:19pm

So was I, but it fits a treat.
I don't understand Brucey's point of view. Never ever had a gear outer "collapse" or heard of it before.

I've just fitted a length of old Campag Ergo gear cable to the rear section on Moulton, and it's fantastic! The rear brake-feel is so much better. Total length of the rear brake outer was 17ins. It had to be that length - and I've shortened it since original - due to the convoluted bend, and any shorter it would have been strained.
By using the stiffer gear Ergo outer, I've got it down to 14ins.

Yes, stiffer and more feel. Similar feel to Mercian now.

Yet to do a test ride, but I'm very confident indeed.
Mick F. Cornwall

alexnharvey
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Re: Compressionless brake housings for cable discs.

Postby alexnharvey » 11 Aug 2018, 3:58pm

:roll: Total madness Mick. :shock:

Does't take much looking to find some pictures of failed gear outers. I wouldn't like to be braking with them

Image

https://www.aquabluesport.com/blog/buye ... ables.html

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Mick F
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Re: Compressionless brake housings for cable discs.

Postby Mick F » 11 Aug 2018, 4:06pm

What do they fail for?
Why do they fail?
What make were they?

Never ever ever had any fail on my bikes. Going back decade after decade after decade.
Mick F. Cornwall