Twin leading link brake adjustment - any advice?

[Guy Wilson]

I'm trying to set up a twin leading link brake as fitted to the 1969 TR6 etc. I can't seem to get a sufficient amount of adjustment on the cable that allows the brake lever to deliver enough leverage to be effective.
The best I can get is the brake lever travels the full distance until it contacts with the throttle. The brake seems to be biting from the moment the lever is pulled, but then is spongy all the way until the the lever touches the throttle. The bar linking the two brakes is fully extended on the adjuster and the two adjusters on the cable, one mid way on the cable and the second on the brake lever almost fully adjusted.  I've tried a couple of new cables. The inner cable is about 8 inches longer than the outer which is correct, the shoes are good with about 4mm of liner etc. the two seats are there on the non-leading link end of the shoes.
The Haynes manual is suitably vague of course and not very helpful
As it is, I would trust it to stop me under any sort of load.
Does anyone have any advise on how to set this sort of brake up correctly? Have any of you experienced this before? I can't see that I'm doing anything wrong although the results suggest I am,
As always, I'm grateful for any input!
Many thanks
Guy
Kenya

[Ethelred]

I don't think there's a 'right' cable for this as the TLS wasn't fitted to the A7/A10, so it's bound to be a bit DIY. I had a similar problem when I fitted mine recently and ended up by shortening the inner by moving the brake lever nipple down a bit. You just need a blowlamp, one of those little butane ones for modellers are good and available cheaply on ebay, and some acid-core solder which is a bit harder to find, but good ole ebay turned up trumps for that too. It was my first adventure into the arcane world of cable making, but all turned out fine and was quite straightforward.

[Guy Wilson]

Thanks Ethelred,
I neglected to say I have the TLS on the Triumph forks and so there should be no DIY involved working out lengths etc. On the face of it the inner cable is too long (or the outer too short) as all the adjusters are at maximum. It led me to think I had set the internals up incorrectly although I can't see how. there just seems to be too much movement on the mechanism etc
I hear you though and really need to get into making my own cables. I'm nervous about at DIY front cable though as its the only one you really need to hold together at that important moment...
thanks
Guy

[A10Boy]

I have a TLS on my A10. To set it up first disconnect the link rod between the two actuation levers. Pull both levers into the "on" position by hand. Now, is the link rod still the correct length? If not, adjust it so it is and refit. Now when one actuation lever is pulled into the "on" position, both shoes are contacting the drum together.
Now, fit your cable, beware there are two types of TLS backplate, one has the cable dropping down the leg and the other has the cable coming in horizontally, I would guess the later has a longer cable.
There is nothing special about this, its the same STD set up whether its fitted on a 58 A10 or a 65 Bonnie or an A65. The only thing that would affect the set up is if the linings were worn out.

HTH

Andy

[duTch]

 Andy are you referring to the Conical TLS as the 'other', which is a totally different setup...??

 Guy, can you maybe move both the brake arms around a notch anti-clockwise on the splines ?

[A10Boy]

No, I'm not referring to Conical. There are two types of TLS backplate that look similar, one has the cable dropping down the leg and the other has the cable coming in horizontally, Google and you will see.

Don't move the levers, I think they are on squares anyway.

Guy, set it up as I suggest and it should be ok, and make sure you have fitted the levers correctly, google a pic

[Guy Wilson]

The TLS I have is the type fitted from 1969 with the cable coming vertically down the fork leg. Its not the later conical type..
I'll try the A10boy method. There maybe a lightbulb at some point, thanks guys, I'll let you know if I begin stopping..
Guy
Kenya

[A10Boy]

The thing is you need both shoes contacting the drum equally. Without properly adjusting the link rod they won't, one will contact before the other and it will only be a one shoe brake and pretty useless.

If you adjust it as previous post, they will both contact the drum together and equally. BTW, that type has a short and a long lever, the link rod fits into the long link in the hole as per the short lever, the outer hole is for the cable. The long lever fits furthest away from the cable retainer. Obviuosly, as all brakes they need to bed in to the drum to work at max efficiency.

HTH

[Guy Wilson]

Thanks Andy, the link rod adjustment is new to me. I'll try it on the weekend,
thanks to you all,
Guy

[Guy Wilson]

can anyone tell me what the liner thickness should be? Mine look fine, but it could be affecting the set up,
thanks
Guy
Kenya

[A10Boy]

Which type do you have, rivetted or bonded? I have some new bonded ones in the shed, the material is approx 5mm thick, these can wear down to about 2mm before they need changing, the rivetted ones need changing  just before the rivet heads are exposed and touch the drum. They also start out at 4-5mm thick.

I'm assuming they TLS brake is new to the drum and therefore will need bedding in. Has the drum ever been skimmed to remove ovality do you know?

[Guy Wilson]

Thanks Andy, I think they are riveted and the lining thickness is as you describe, certainly not less than 2mm. The drum is currently on my TR6 and has been there for 15 years or so. I used it regularly up until about 5 years ago when the front cable broke and work and other things had me not replace it...so about a month ago I got round to replacing it and that's when the drama started. I bought the correct cable after the one I had didn't take up the adjustment, but I still couldn't get it to bite properly. The TLS are pretty good when set up correct and I tend to rely on the front brake more than the rear, so I wanted it working as it should..

I seem to remember I had an adjuster or an extension on the back plate which is how I got the adjustment last time. I suspect the culprit is the cable length but it seems odd that its too long as it seems to meet the specs. (inner cable is about 8'' longer than the outer)

All the internals are good and grease and move freely, so I was banging my head a bit to figure why it wasn't working. I'll try your method adjusting the connecting rod before I go any further.
Guy

[Rocket Racer]

A10boy is spot on the money, it is essential that the rod length is set carefully, otherwise one shoe will not function and you are wasting your time with a TLS.
Both levers should contact at the same time and the rod length adjustment facilitates this.

[Ethelred]

"I seem to remember I had an adjuster or an extension on the back plate which is how I got the adjustment last time"

I think you've just answered your own question there. Have you got an adjuster on the lever? Is there an in-line one on the cable?
The standard Triumph TLS backplate doesn't have provision for an adjuster so yours might have been adapted for one if your memory is correct.
Assuming you've now done the link adjustment as described by A10Boy there's only cable length left. I refer the gentleman to my previous reply 

[Guy Wilson]

the adjuster on the back plate was something I put there out of frustration. My BMW was off the road and in bits and I needed a bike that went and stopped. It was never 100% perfect
It had an adjuster on the lever but I don't seem to remember an inline adjuster as well. Putting third adjuster on the back plate seems like a bridge too far and not how it was designed to work.
I suspect the inner cable length is too long by about an inch. I'm going to have a go at making my own cables. It seems to be the way forward...
As always, thank you for your valuable input.
Guy