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.
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.
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.
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
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.
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.
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.
I meant 39 ins, not 36.
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.
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.
Unfortunately Draganfly don't have a cable to match my old one. Any ideas please as to where I might get one?
Phil.
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.
Where would be a good place to gather materials? Phil.
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.
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
if it rattles, its more likely to wear due to vibration , a nice sliding or tighter fit but not an interference (hammer in) fit as too tight can damage the cable
Reality is the photo below. The bent steel ones vary.
Photo shows shackles cropped from cables over the years.
The only one which is a close fit is the one top right which came from an old A10 cable.
Ready made cable quality can be questionable, look at the prices - you can buy an imported front brake cable from ebay sellers for less than £7 including postage.
The one on my old (existing) cable is like the one top right of your photo's, Julian, and fits on the arm okay. Chaz confirms what I thought, ie a decent fit is needed, rather than a rattling one.
Anyway, to recap: my bike is 1965, but the brake cable which is listed, and sold, for that year (part no. 41-8535) appears to be wrong for my bike (too long, ie 39 ins outer cable, and clevis fork a very loose rattling fit on my actuating arm, like about 2mm wider than the arm thickness.)
The old (existing) cable appears to fit the bike fine. It is, I think, about the same length as the cable listed for 1960-64 bikes (part no. 41 - 8505) (32 ins outer cable.)
I wonder if the shorter (41-8505) cables have a smaller clevis gap than the longer (41-8535) ones. I'll phone a dealer on Monday morning and check.
I'm thinking maybe my 1965 bike takes the cable designed for the previous year's bike (41-8505, the 32ins type.) That would seem a bit weird. Why would it be? Phil.
Like Phil, I am finding this frustrating. The RR books says you can just a cable off the shelf.....but if you do you'll end up with a cable that is far too long (as Phil's photo illustrates). I also can't fathom why the cable for 65-66 B40 became 7" longer, than the earlier B40 Star's
On my B40f(Sept 64 B40f star - aka '65' model) I can't quite adjust my cable so it starts to bite more or less as soon as I start pulling the brake...to get that tad further the barrel adjuster is no longer in it's recess on the bars. Measuring: my outer is 31" and the pivot to pivot point inner cable length is 38"
My conclusion is I need a difference between the inner and outer of 6", rather than 7" to allow me to adjust the brake correctly, with 32" outer, 38" inner being being a doable length...i.e as 1964 and before B40 Stars (with non-western handlebars). Both could happily be an inch longer ( BUT not the bizarre "official" listed cable length.
I am going to have to phone up suppliers tomorrow as so far I am not finding anyone listing both the outer and inner cable which seems just as important as citing the outer length. ( Grrrhh!)
Why not get jj cables to make you one to your spec.
Why not make one up yourself? Guaranteed to fit perfectly.
Quote from: V500 on 23 Jan, 2025, 09:06 Why not make one up yourself? Guaranteed to fit perfectly.
As I always do. Brake cables are easy - more than throttle for example - as it's easy to measure exact dimensions. But of course carry greater risk if your technique's not up to snuff.
Venhill will make you a canle to your specifications.
https://www.venhill.co.uk/bespoke/cables/
... although not cheap. I bought materials for clutch, throttle and choke from them for more or less that price.
Probably not up to snuff to make my own.
Adding a 2nd barrrel aduster (of the cut ring type) at the other end seems a cheaper option than a made to measure cable.
I bought several front brake cables for my C15 project - all seemed to be far too long. Eventually I made a clamp for birdsnesting the cable end, and cut one down and resoldered. Then I discovered some old BSA pictures, which show that the C15 front brake cable should be routed over the headlight nacelle to the left side of the bike, then back across the top of the mudguard and down. (IIRC, the clutch cable does more or less the reverse.) So almost certainly all the cables I rejected as too long were in fact perfect.
Ah Ha...that'll be it then. Just been googling and found a couple of post-65 pics showing that routing. I'll consider if I can get my head to like it!!
(currently the lever almost gets to the bar when I brake, so probably do need to find a better action)