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Bowdenex Brake Cable Refitting

Hi Folks,

I've been refurbishing the front axle on my special and now need to reattach the bowdenex brake cables.

Does anyone have any tips for fitting them? I've struggled to get both ends on as the cable could do with about one inch of additional slack.

Any tips would be appreciated!

Thanks.

Matt

Location: South Derbyshire

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Re: Bowdenex Brake Cable Refitting

Don't.
Revert to the original system having bought a complete set of new parts with high friction linings.

Location: Bristol

Re: Bowdenex Brake Cable Refitting

ditto

Location: oz

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Re: Bowdenex Brake Cable Refitting

Bowdenex. - Heavy, inefficient and never work correctly. Go back to the original Austin set-up with short levers on the front brakes and the cams positioned at the bottom of the hubs.

Location: Moseley

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Re: Bowdenex Brake Cable Refitting

Agree with Terry and Ian. There's nothing wrong with standard brakes other than excessive wear and incorrect adjustment.

Re: Bowdenex Brake Cable Refitting

However, if you are committed, if there's enough spare length, you could get the extra inch you want on the inner cable by shortening the outer by a similar amount.

Re: Bowdenex Brake Cable Refitting

I have bowdenex brake cables on the front of a special and they are pretty useless,as others have said drag in the cables and weak outer cable brackets contribute.
Has anyone tried Twin leading shoeing or self servoing or similar to improve the brakes and are prepared to share their knowledge ?

Location: Channel Islands

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Re: Bowdenex Brake Cable Refitting

Quote: Austin in the shed
Has anyone tried Twin leading shoeing or self servoing or similar to improve the brakes ... ?
I think Ian TIllman at Oxfordshire Sevens has done some work on this.

Re: Bowdenex Brake Cable Refitting

I can't see how you can TLS an A7 brake as the king pin boss gets in the way,only self servo.Looking on a bike web site someone had altered a BSA gold Star SLS but from what he says it was probably prone to snatching when applying the brake.
I hoped for curiosity if the 7" brakes can be improved without grafting on hydraulics.

Location: Channel Islands

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Re: Bowdenex Brake Cable Refitting

AiS,

from an old post on here:

Quote: PGS
As Peter mentioned I manufactured a TLS conversion for my special but it uses few original parts. The reason for having four shoes was to make use of a motorcycle component that's available in the correct diameter.

The car is nearly finished but I've yet to try the brakes!

Regards Bernard

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Re: Bowdenex Brake Cable Refitting

I am surprised at the lack of enthusiasm for the Bowdenex conversion. Over the years I have run three Sevens with Bowdenex brakes, and my rose-tinted spectacles suggest they were the ones with the best brakes.

Sorry, Alan, 'nothing' wrong with standard brakes? I'm not an engineer, but surely there are at least two fundamental things wrong with the standard brake design?

Firstly, with a pendant brake lever pulling backwards, any twisting of the king-pin inclination due to braking effort results in a negative servo effect, requiring an increase in pedal movement/pressure just to maintain existing braking. Secondly, pulling the brake lever with a cable running at 45° to the action of the lever is just plain bad design; it's bad enough when the steering is in the straight-ahead position, but on full lock the outer wheel requires the cable to pull at almost 90° to the desired movement (incidentally, has anyone ever tried cables operating round pulleys fixed to the back-plates, as used on Riley Nines, which would alleviate this problem?).

The Bowdenex conversion successfully addresses both of these problems. To condemn it because of stiff cables resulting from poor maintenance is hardly a fair criticism.

If anyone is thinking of discarding their Bowdenex system as a result of this thread, I am only too happy to receive their unwanted scrap!

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Re: Bowdenex Brake Cable Refitting

Mike,
I have fitted them on my new special. I will report on their superior qualities (or lack of!) when it is on the road.
Cheers,
Dave.

Location: Sheffield

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Re: Bowdenex Brake Cable Refitting

I have kept quiet so far but I will come out as one who finds Bowdenex perfectly satisfactory when correctly fitted and maintained.
A really common experience with existing installations is to find that a former owner, faced with a grease nipple on the outer cable, has greased it. Fatal! Hanging up the cable and treating it with a hot air gun for a while helps no end with the cable drag induced by the grease. And as Michael says, it overcomes several small nastinesses.
I am the first to admit that a well set up standard system with soft linings and a suitable flexible brake cable can work very well.
Regards,
Stuart

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Re: Bowdenex Brake Cable Refitting

Hi All,

This thread seems to have wandered off in the wrong direction.

Rather than bang on about the merits or issues with the Bowdenex cable system, could Friends please answer my original post question?

Many thanks,

Matt

Location: South Derbyshire

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Re: Bowdenex Brake Cable Refitting


Hi Matt,

Have you tried taking the drums off, pulling the brake levers on to 90deg to refit the clevis ends, (might also help to remove the bracket from the cross member and feed the outers in before refitting) then release the levers and refit drums. Just a thought.

Tom

Location: Eye on the Norfolk / Suffolk border

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Re: Bowdenex Brake Cable Refitting

Quote: Mike Costigan
If anyone is thinking of discarding their Bowdenex system, I am only too happy to receive their unwanted scrap!


Hi Mike,

I have a set you are welcome to - if you are happy to pay the postage I will send them on to you.

Stuart had a set from me like this just last year.

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Re: Bowdenex Brake Cable Refitting

Hi Everyone,

Thanks for your feedback.

I have now managed to reattach the Bowdenex cables and in the end it's really simple when you know how!

First feed the brake cables into the special brackets on the brake cross tube. Just add one of nuts to the threaded end of the cable.

Next, at the front of the car, take the cable sleeves out of the bracket/slot on the hub back shells. Put the pin through the cable clevis and brake lever arm. Fit the split pin.

Now the easy bit, gently pull the cable sleeve up and relocate the cable into the hub back shell bracket.

Adjust the cable tension under the car at the cross tube and fit the locknut. Adjust the brake shoes.

Job done.

Location: South Derbyshire

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Re: Bowdenex Brake Cable Refitting

Just a thought regarding Bowdenex type brakes, Many if not most modern hand brake cables have an inner liner of either nylon or ptfe type material in their construction to ease the friction. has anyone tried these as an alternative to the original steel cable within a steel sheath.

Location: Piddle Valley

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Re: Bowdenex Brake Cable Refitting

The Bowdenex that came with our Type "65" was more than a little sticky. Washing it in solvent and running oil into it improved the action somewhat, but a close inspection of the cable showed flat spots on the weave or braid of the cable, which was causing a lot of drag inside the outer housing.

We took the cables into our local Cableman who made up suitable replacements, Dad machined up some new fittings and the result was so good that we made another set for our single seater special which stopped really well at the Simola Hillclimb last year.

Currently close to completing a new supercharged single seater, we've had a third set made for it and I'll run them in at Simola this year.

Aye
Greig

Location: Sunny South Africa

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