Brake cable length

[Phil C]

Received my new front brake cable this morning, comprising inner and outer, with attached nipples and clevis fork.

I notice it is about 7 inches longer than the old one, which seems quite a difference.  Is there a specific recommended length? (1965 B40F)

Phil.

[AdrianS]

I ended up making my own ( shortening an existing long one at the nipple end). They all seem to vary in length. The last one I bought was far too long so I shortened it myself. Quite easy to do if you have got a Dremel to carefully cut the outer sheath off and a small blowtorch to melt the solder in the nipple.

[Phil C]

Interesting, Adrian. I wonder how much you had to shorten yours by.

I don't have a dremel, nor a blow torch. Anyone know what the length should be?

Phil.

[berniej]

I think that there were at least two standard lengths for some models - my B40B, repatriated from the U.S. - has higher bars and hence a longer cable - maybe you received an export cable?

Cheers,
Bernie

[JulianS]

Ready made cables are usually a compromise size.

The ideal length really depends on your bike - wear on the linings and drum the handlebar lever used etc. The outer needs fit between handle bar lever and cable stop on the brake plate with a smooth run and with enough length to allow the forks to extend without applying the brake and with out excess length which will make for a spongy brake. The inner needs to be long enough to allow for adjustment at the handlebar. If the inner is too long you wont be able to properly adjust it.

The old Clarks cable catalogue gives the outer length for B40 1965 as 39 inches and 42 inches with western bars. No inner length given.

Some ready made cables have nipples of moulded solder which obviously just melt if heat is applied. The original type were fitted with brass nipples, cable end formed into a birds nest shape and then soldered in place.

[Phil C]

Brilliant. This forum is a mine of information!

Thanks very much, chaps. Just measured my outer cable and it is about 39 inches, so I guess that's right then!  The old one must have been a bit on the short side, I suppose.

I can now settle down contentedly to my Saturday night (lamb tagine in the oven, bottle of red close at hand, winking at me.)

Phil.

PS How things change as we get older. I mean, forty years ago any thought of "settling down" on a Saturday night would have filled me with gloom.

[Phil C]

I'm aware that I'm a raw novice in this hobby, but I thought that replacing a brake cable would be fairly straightforward. I'm beginning to think I was mistaken.

The book says (thanks again Julian) that the outer cable should be 36 ins long, and that's what I have been sent by a reputable dealer. So that seemed okay, although I couldn't understand why the old one was about 7 inches shorter.   Now when I offer the new one up to the bike, it seems far too long (see photo attached.) Any thoughts please? It's much too long, isn't it? Looks like the old one is closer to a suitable length. But how can this be, given that the book says 36 ins, and the dealer has sent me one that length?

Also, the clevis fork (is that what it's called?) on the new one has a gap of over 7mm, whereas the thickness of the actuating arm (is that what it's called?) that the fork fits over is only 5mm. Surely the fork should slide snugly over the arm?  I guess I could shim it out with washers, but surely the clevis fork should be a good slide fit?

So not going too smoothly at the moment.  Any advice please?   Phil.

[Phil C]

I meant 39 ins, not 36.

[JulianS]

Not unusual to find cables dont fit. If you use that one I expect the brake will be somewhat spongy. I suggest send it back for a refund.

It is why I always make my own cables and reuse the fittings.

For information I have attached the page from the Clarks catalogue, note the difference between up to 1964 and after.

Second attachment comes from the Trader Handbook, 1961 issue, and shows cable dimensions for that year.

[Phil C]

Mmm, thanks Julian. Looking at the extract from the Clarks catalogue, I see the difference in length between 1964 and 1965 is 7 inches, which is the difference between my old cable and the new (too long ) one. So I wonder if, for some reason, although my bike is 1965 (side points model), the cable length should be as per 1964 models? Why would there be such a difference in length of cables between 1964 and 1965?

I also wonder if a 1964 cable would have a proper size clevis fork for my actuating arm. I'll phone the supplier tomorrrow and check. Looks like they sent me the correct cable in theory for a 1965 bike, but in practice it doesn't fit.

On a slightly separate note, my CLUTCH cable takes a route from the hand lever, over the top of the headlamp (near the clock) and back down under it, across to the left hand side of the bike, before crossing again to the little elbow arm on the right hand side near the gearbox. I wonder why it goes across the top of the headlamp? Too long a cable maybe? Or is that the standard route for a clutch cable?

Phil.

[Phil C]

Unfortunately Draganfly don't have a cable to match my old one. Any ideas please as to where I might get one?

Phil.

[JulianS]

You could try the earlier cable, 1962-64;

https://www.ebay.co.uk/itm/BSA-B40-FRONT-BRAKE-CABLE-1960-64-41-8505-UK-MADE/254313995177?hash=item3b364b9ba9:g:MpoAAOSw

There are several suppliers of tailor made cables who advertise in Old Bike Mart.

J J Cables 01926 651470

Carrot Cycles who have a website.

You could phone C and D Autos who are very helpful -01564 795000.

You could gather the materials and make your own.

[Phil C]

Where would be a good place to gather materials?   Phil.

[JulianS]

Venhill products good quality. They also make cables.

https://www.venhill.co.uk/cables-amp-components.html

Vehicle wiring products;

http://www.vehicle-wiring-products.eu/section.php/148/1/control-cables-and-fittings

Many more suppliers I expect.

[Phil C]

Am I right in thinking that the clevis fork should be a nice sliding fit over the brake actuating arm? I mean, you wouldn't fit one with a rattling fit like a mm or two play, would you?   Phil