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8 SLS performance #718002
12/07/17 7:11 am
12/07/17 7:11 am
Joined: May 2017
Posts: 51
Gothenburg, Sverige
T
TrophyTR6 Offline OP
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Joined: May 2017
Posts: 51
Gothenburg, Sverige
Hello! Sorry to yet again ask a newbe question. I hope that I one day can give something back to this forum.

When searching and reading about this subject I have understood that the triumph 8 also brake isn’t show stopper but can it be as bad as mine or is something wrong?

Some background: I bought the bike (-59 TR6) this summer but haven’t ridden it yet properly. One reason being that’s imported from the UK and still isn’t road legal here in Sweden and the other that I have been rebuilding the engine and transmission. I have also gone over most of the bike and replaced parts where needed.

One such part was the front brake that I thought was a bit tired ( barely working). I replaced the brake shoes but apart from that everything else looked fine. After a very short ride this winter (2 kilometres) I noticed that the front brake still wasn’t performing at all. I took the brake apart the other day and found a lot of dust from the brake shoes, a lot more than you would expect from such a short ride. The big clue to the bad performance (and the brake dust) was that I had put the brake shoes on the wrong way. The right part of the shoes were at the right side of the fulcrum and pivot pin but I had them switched. I cleaned everything and put them back the right way. But still the same poor brake performance. I took everything apart again and lined the inside of the drum with adhesive sandpaper to match the shoes with the drum. After carefully “grinding” away some of the shoes I took everything apart again, cleaned and rebuilt. Loosened the fulcrum, squeezed the lever and tightened the nut. Now there were some improvement but the brake are still so bad that it’s dangerous. If I pull the lever really hard the bike will stop eventually but there’s no “bite” ( the bike is just rolling down a small slope, no engine running) . It just sounds like the shoes are slipping/dragging on the inside. My previous encounters with drum brakes are that even if they are bad, if you pull hard enough they will “bite”. But these aren’t. I can’t even get my front to “bow” when I squeeze the handle all I can. It just slips!? The bike would probably stop faster if I dragged my feet on the ground

I include some pictures, maybe someone sees the problem. The brake drum to seems ok. One can see that it has been machined/skimmed (is that the right word) in the past but it’s nice and flat. I also had an idea that maybe the pivot and fulcrum pin were for another model and that they are causing the problem but upon inspection they seem to be in good nick and looks like the parts in the parts book. What to do?

/ Chris


[Linked Image]
[Linked Image]
[Linked Image]
[Linked Image]


Last edited by TrophyTR6; 12/07/17 7:14 am.
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Re: 8 SLS performance [Re: TrophyTR6] #718007
12/07/17 8:39 am
12/07/17 8:39 am
Joined: Dec 2004
Posts: 9,332
Scotland
kommando Offline
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Scotland
If the drum has been skimmed in the past then you need new oversize linings arc'd to the drum or made to your measurements for best performance, using std shoes in a skimmed drum will result in contact only in one section of the shoe and a weak brake.

For oversize shoes made to suit the drum and measurement then you can use

http://villiersservices.co.uk/index...r=4&zenid=b7uqd0qk6gcnmu7j6vk5kfhjn2

or

http://www.saftek.co.uk/classics.html

Both have good reviews, you send them your old shoes and tell them the size of your drum ID and the OD of the shoes with no lining fitted, they then fit modern linings to suit those measurements.

Last edited by kommando; 12/07/17 8:40 am.
Re: 8 SLS performance [Re: TrophyTR6] #718009
12/07/17 9:09 am
12/07/17 9:09 am
Joined: May 2017
Posts: 51
Gothenburg, Sverige
T
TrophyTR6 Offline OP
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TrophyTR6  Offline OP
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Joined: May 2017
Posts: 51
Gothenburg, Sverige
Good info kommando! But when I installed the new shoes the first time it was real snugg and there were not much clearance in the brake arm. Could the drum still be to big? In one of the pictures you can se the small edge left from skimming, its very small. I have had bikes with break drums really beaten up from wear and tear and there would still be some bite in it. Are these sls breaks extremely sensitive?

Re: 8 SLS performance [Re: TrophyTR6] #718010
12/07/17 9:17 am
12/07/17 9:17 am
Joined: Dec 2004
Posts: 9,332
Scotland
kommando Offline
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Scotland
Its been skimmed so its bigger and so std shoes will not fit well enough for best braking until they wear in, your pictures do not show much of the shoe lining but the little I can see shows a single line contact, maybe the skimming is not all the way into the corner and the lining is only contacting fully on the inner edge.

Re: 8 SLS performance [Re: TrophyTR6] #718011
12/07/17 9:41 am
12/07/17 9:41 am
Joined: Mar 2011
Posts: 836
derby england
wak Offline
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wak  Offline
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Posts: 836
derby england
Start with the basics , lubricate all pivots and the cable , is the cable a pattern part with a stretchy inner wire? do you have the correct ratio handle bar lever? is the brake fulcrum arm the correct length ? Are you centering the brake plate before tightening the spindle nut , and centering the fulcrum pivot bolt before tightening its nut? .if this all fails maybe the lining material is Asian crap


BSA lightning
BSA B50MX
TRIUMPH TR6C
BSA BUSHMAN
BSA Gold Star Daytona
BSA Gold Star Scrambler
BSA Rocket Gold Star
BSA C15S
BSA Cyclone
Triumph T120
Triumph T100 Daytona
Triumph 5TA Trials
Triumph T100 Scrambles
Cheney 560 TT
Re: 8 SLS performance [Re: TrophyTR6] #718012
12/07/17 9:59 am
12/07/17 9:59 am
Joined: Jan 2007
Posts: 552
Queensland, Australia
T
Tiger100 Offline
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Joined: Jan 2007
Posts: 552
Queensland, Australia
After completing my pre unit bitsa (with sls) I gave up on trying to improve its braking capacity...it was woeful and didn't seem to matter what I did to improve it. so I fitted a tls from a late 60s triumph I had years ago and haven't looked back, it works and works very well.


Regards

Grant
Re: 8 SLS performance [Re: TrophyTR6] #718018
12/07/17 12:42 pm
12/07/17 12:42 pm
Joined: May 2017
Posts: 51
Gothenburg, Sverige
T
TrophyTR6 Offline OP
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TrophyTR6  Offline OP
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Joined: May 2017
Posts: 51
Gothenburg, Sverige
@kommando; The skimming seems to be all the way in, at least good enough for the brake shoes to only touch the new surface. I have tried to show the edge with the arrow in the picture below

@wak; Cable are new and a good quality one, brake lever are the correct one. Brake fulcrum arm seems to be the correct one when i look in parts book and pictures of other TR6. When you engage the brake at stand still it feels very good and there are a distict feel to it, no flexing or sounds or anything.
"Are you centering the brake plate before tightening the spindle nut". Not sure what you mean by this. I don't loosen the pivot pin only the fulcrum pin when I reassemble. The brake shoes are from LF Harris, really dont know if they are good quality or not. If you google W1410 it seems to be the only ones coming up.

@tiger100; I really want to keep the bike stock looking, its pretty much restored to original / new.

[Linked Image]

Last edited by TrophyTR6; 12/07/17 12:51 pm.
Re: 8 SLS performance [Re: TrophyTR6] #718076
12/07/17 8:28 pm
12/07/17 8:28 pm
Joined: Jun 2007
Posts: 5,854
Maui Hawaii
HawaiianTiger Offline

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HawaiianTiger  Offline

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Posts: 5,854
Maui Hawaii
I feel your pain. My favorite bikes have these brakes installed from new. Pathetic is the best description. Of all the ones I've worked on or owned, only two had what I consider to be marginally adequate braking.

One was a chopper and considerably lighter than a stock bike.

It had the original linings from new, rock hard but the bike actually stopped OK.

The other had custom made lining from a vintage car racing brake shop. They installed carbon fiber linings. Initially the brake would work very similar to original linings but as they warmed up in use, they became progressively better and better until I could lock the front wheel up.

So I feel the solution to the problem is either to install some custom or later brake, or to install linings from a shop that specializes in drum brakes. Also, have the whole wheel chucked up and the drum skimmed, not just the drum. The drum will go oval on you when the wheel is laced up.

There are other considerations as well. The levers you have may not be right for your brake. On a brake like this, you want all the leverage you can get. Check the pivot bolt to nipple distance. It should be less than one inch, like 5/8" or 3/4". If over one inch there won't be adequate leverage for this brake.

Cheers,
Bill


Last edited by HawaiianTiger; 12/07/17 8:37 pm.

Bikes
1974 Commando
1985 Honda Nighthawk 650
1957 Thunderbird/T110 "Flying Tiger"
Antique Fans: Loads of Emersons (Two six wingers) plus gyros and orbiters.
Re: 8 SLS performance [Re: TrophyTR6] #718115
12/08/17 9:45 am
12/08/17 9:45 am
Joined: Sep 2008
Posts: 778
Skudeneshavn Norway
S
Stein Roger Offline

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Stein Roger  Offline

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Joined: Sep 2008
Posts: 778
Skudeneshavn Norway
I bought my first Triumph, a 1958 T110 in 1975. The first thing that happened to me was that the primary chain broke and had me off in front of hundreds of people. The next was that the front cable broke and landed me in the rear of a car. Well, not landed actually, but I hit his bumper enough to wake him up. He was a good sport and was more interested in the damage to the bike than to his car though. Both hardly noticeable, I was lucky.
Enough story telling, the point was that these things taught me that riding motorcycles is great fun, but not without some risk, and I'd better shape up and get ahead on maintenance to mitigate the mechanical ones at least. After all these two crashes were due to the state of my vehicle, not my driving.
So I promptly changed the cable and riveted on new linings on the brake shoes. And voila!... but no... almost no brakes at all. Upon inspection I saw that the linings hadn't yet bedded in, merely touched the drum at a few spots here and there. So I set forth and sanded down the high spots by hand, one by one, re-installed and tried again. I can't recall how many times I had to do this, but it took a lot of time and effort. It was totally worth the effort though, the brake became very good indeed, I could even lock the front wheel at moderate speeds and have the tire squealing at higher speeds if I pulled the lever really hard. It never became anything like the later brakes but acceptable and pretty safe.
I'm sure outfits like Vintage Brake, Villiers or Saftek can go a long way in making your brake work well but the final touch may sometimes give them an edge.
On my Trident with the conical nave, the brakes are pretty good but when they start to lose bite, I flush through them with the garden hose. I believe accumulated brake dust acts as tiny ball bearings when wedged between the linings and the drum, and flushing them out will restore the bite. BUT! Until the water has dried out your brake will be useless, when the water has evaporated it will GRAB! and have you off if you're unprepared!
I believe you're on the right path, just keep at it.

Re: 8 SLS performance [Re: TrophyTR6] #718120
12/08/17 1:09 pm
12/08/17 1:09 pm
Joined: May 2017
Posts: 51
Gothenburg, Sverige
T
TrophyTR6 Offline OP
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T
Joined: May 2017
Posts: 51
Gothenburg, Sverige
Thanks Bill and Roger! appreciate your feedback. I still really cant get my head around how these brakes can be so bad? They look really beefy and nice with floating shoes and all.... well well I just have to let go of my disappointment.

@Bill; I will check the brake lever but I think its the one its supposed to be. If my efforts getting the brake better with what I have I will definitely look up someone who can advice me on some other brake linings and / or skim the drum again.

@Roger; Sounds really good you got your brake working properly, I will continue tweaking and hopefully it will get better.

Cheers/ Chris

Re: 8 SLS performance [Re: TrophyTR6] #718123
12/08/17 1:54 pm
12/08/17 1:54 pm
Joined: Feb 2012
Posts: 130
Wiltshire England
D
DUHC Offline
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Joined: Feb 2012
Posts: 130
Wiltshire England
Luckily I haven't had this problem with new bike brakes, but I certainly have with new brake shoes on the rear of my MGB where the handbrake would not hold the car. Picking up on Roger's point the solution was bedding them in. The new linings have to adjust to the shape of the old drum. Easy enough in a car. I drove it for a few miles with the handbrake partially on, then readjusted brakes. Voila! Good brakes. Could you ride your bike (as much as you can legally) with the brake adjusted so that the shoes were as near as possible touching drum, and then go for a ride, and then re-adjust?

Re: 8 SLS performance [Re: DUHC] #718133
12/08/17 4:06 pm
12/08/17 4:06 pm
Joined: Sep 2008
Posts: 778
Skudeneshavn Norway
S
Stein Roger Offline

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Stein Roger  Offline

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Joined: Sep 2008
Posts: 778
Skudeneshavn Norway
The downside to running with the brakes on is that you can overheat, or "cook" the linings, which will destroy them. Owners manuals used to specify how to run in, or "burnish" the brakes, the information is still easily found on the web. It involves numerous brake and let cool cycles and part of the process is to permanently alter the composition of the brake friction compound. A sort of curing process if you will. It will also mate the surfaces, but that depends on how high the high spots are and so on.
Sanding them is a good DIY way to achieve a good fit. High spots will appear as polished areas against the matte surface of the lining.
It's important to let the brakes cool between applications. This is how I did it over 40 years ago, not because I was so smart but it felt right somehow, and later I learned it was.
Dumb luck is better than no luck.

Re: 8 SLS performance [Re: TrophyTR6] #718146
12/08/17 6:41 pm
12/08/17 6:41 pm
Joined: Jun 2007
Posts: 5,854
Maui Hawaii
HawaiianTiger Offline

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Posts: 5,854
Maui Hawaii
I wanted to add another item to the list to check.
A lot has been written here about the conical brake(BSA designed item) fitted to early 70's Triumphs, nicknamed "Comical' brake by some because of how poor these brakes function.
I had one in my shop this year and one of the things the owner wanted me to address was the poor performance of the front brake.
I had it apart, carefully inspected it, replaced the shoes, properly assembled it only to have it perform exactly the same; very poorly.

Looking at the cable, I saw it was of a rather small diameter and had a brake light switch in line. I dug around in my old parts and found a Norton clutch cable. This thing was massive. A bit of overkill, but I modified it, installed that bugger and the brake was transformed. Not a disc brake, but on a par with your basic 68-70 TLS brake.

If you manage to make this front brake perform satisfactorily, you should consider sharing the secrets here for others to learn from.

Cheers,
Bill


Bikes
1974 Commando
1985 Honda Nighthawk 650
1957 Thunderbird/T110 "Flying Tiger"
Antique Fans: Loads of Emersons (Two six wingers) plus gyros and orbiters.
Re: 8 SLS performance [Re: TrophyTR6] #718151
12/08/17 7:17 pm
12/08/17 7:17 pm
Joined: Aug 2001
Posts: 7,432
scotland
triton thrasher Offline
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Joined: Aug 2001
Posts: 7,432
scotland
[Linked Image]

That looks like an unfortunate design of brake.

The trailing shoe’s lining extends nearer to the cam, than that of the leading shoe, so the trailing shoe meets the drum and stops the cam turning, so the leading shoe doesn’t get more pressure as you squeeze the lever harder.

The direction of cam rotation will exacerbate that same effect, because the lobe nearer the fulcrum imparts more movement and that’s the lobe that’s operating the trailing shoe.

These effects may be mitigated to some extent by the floating shoes, but complaints about Triumph SLS brakes are rather common.


Amateur Loctite enthusiast.
Re: 8 SLS performance [Re: TrophyTR6] #718164
12/08/17 9:15 pm
12/08/17 9:15 pm
Joined: Jun 2007
Posts: 5,854
Maui Hawaii
HawaiianTiger Offline

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Posts: 5,854
Maui Hawaii
Perhaps that's the reason the hydraulic conversion done by some folks results in a better brake. Hydraulics tend to equalize pressure on both shoes. But the force applied is only a factor of ft pounds and leverage.

Cheers,
Bill


Bikes
1974 Commando
1985 Honda Nighthawk 650
1957 Thunderbird/T110 "Flying Tiger"
Antique Fans: Loads of Emersons (Two six wingers) plus gyros and orbiters.
Re: 8 SLS performance [Re: TrophyTR6] #718200
12/09/17 5:50 am
12/09/17 5:50 am
Joined: May 2007
Posts: 1,982
Christchurch NZ
R Moulding Offline
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Christchurch NZ

Apply some adhesive backed coarse sand paper to the drum, assemble the brake plate into the drum with the top pin loose. Apply brake to centralise shoes and hold whilst you tighten axle nut and top pin. Spin the wheel whilst applying light pressure. Disassemble and inspect shoes for low spots, continue until there are none. Remove sand paper and try.

Rod


So remember, when you're feeling very small and insecure,
How amazingly unlikely is your birth;
And pray that there's intelligent life somewhere out in space,
'Cause there's bugger all down here on Earth!
Re: 8 SLS performance [Re: TrophyTR6] #718211
12/09/17 9:59 am
12/09/17 9:59 am
Joined: Sep 2008
Posts: 778
Skudeneshavn Norway
S
Stein Roger Offline

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S
Joined: Sep 2008
Posts: 778
Skudeneshavn Norway
TT, yes complaints are common and once you've sampled a later TLS, that's what you'd want to have, discs aside. I'm currently modifying 58 SLS to a Bendix Duo-Servo type of thing, that'll be interesting. I have a 67 Bonnie here with a decent SLS brake, but it has the wider linings that came in 66 I believe. It has good stopping power but it takes a while to build up. Like there's a built in delay somewhere. I hope cleaning and lubricating will sort it.
My former wife had a 3TA with a 7" brake that simply defied anything I did to it, sometimes these things simply beat me. I can't believe they used the same brake on the 6T.

Bill, my Conicals were always good brakes, provided you kept them in adjustment, changed the brake cable switch for a solid piece, or, as on my current Trident, replaced it with a new beefy cable without it. I ordered mine directly from Venhill. I have extended the brake arms 35mm, but in the light of experience I'd say 25mm/1" should suffice. It made a big difference anyway. Periodic cleaning with water as mentioned before usually helps a lot.

Rod, I've always wanted to try that but never did. Do you have first hand experience with this? I'm thinking that the thickness of the sand paper would make the lining radius slightly smaller than the drum, or is the difference so small as to be negligible?
How about fixing sand paper to the linings to freshen up the drum, have you tried that?

Re: 8 SLS performance [Re: TrophyTR6] #718213
12/09/17 10:22 am
12/09/17 10:22 am
Joined: Aug 2001
Posts: 7,432
scotland
triton thrasher Offline
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Joined: Aug 2001
Posts: 7,432
scotland
Wanna see something scary?

[Linked Image]


Amateur Loctite enthusiast.
Re: 8 SLS performance [Re: triton thrasher] #718215
12/09/17 11:03 am
12/09/17 11:03 am
Joined: May 2017
Posts: 51
Gothenburg, Sverige
T
TrophyTR6 Offline OP
BritBike Forum member
TrophyTR6  Offline OP
BritBike Forum member
T
Joined: May 2017
Posts: 51
Gothenburg, Sverige
Originally Posted by HawaiianTiger
I wanted to add another item to the list to check.
A lot has been written here about the conical brake(BSA designed item) fitted to early 70's Triumphs, nicknamed "Comical' brake by some because of how poor these brakes function.
I had one in my shop this year and one of the things the owner wanted me to address was the poor performance of the front brake.
I had it apart, carefully inspected it, replaced the shoes, properly assembled it only to have it perform exactly the same; very poorly.

Looking at the cable, I saw it was of a rather small diameter and had a brake light switch in line. I dug around in my old parts and found a Norton clutch cable. This thing was massive. A bit of overkill, but I modified it, installed that bugger and the brake was transformed. Not a disc brake, but on a par with your basic 68-70 TLS brake.

If you manage to make this front brake perform satisfactorily, you should consider sharing the secrets here for others to learn from.

Cheers,
Bill


Bill! My brake cable is actually exact what you describe. Ordered from the US with the part number as per parts manual, when it arrived it was clear its much beefier (both wire and bowden cover) and I had to modify it to work with my brake lever. I don't think this is my problem.


Originally Posted by triton thrasher
[Linked Image]

That looks like an unfortunate design of brake.

The trailing shoe’s lining extends nearer to the cam, than that of the leading shoe, so the trailing shoe meets the drum and stops the cam turning, so the leading shoe doesn’t get more pressure as you squeeze the lever harder.

The direction of cam rotation will exacerbate that same effect, because the lobe nearer the fulcrum imparts more movement and that’s the lobe that’s operating the trailing shoe.

These effects may be mitigated to some extent by the floating shoes, but complaints about Triumph SLS brakes are rather common.


TT I cant argue with you :-) This is all above my knowledge of breaks and you are probably right about its design.


Originally Posted by R Moulding

Apply some adhesive backed coarse sand paper to the drum, assemble the brake plate into the drum with the top pin loose. Apply brake to centralise shoes and hold whilst you tighten axle nut and top pin. Spin the wheel whilst applying light pressure. Disassemble and inspect shoes for low spots, continue until there are none. Remove sand paper and try.

Rod


Rod! I already tried this, I think I wrote this in my first post. After this the break got noticeable better but far from "working"


Originally Posted by triton thrasher
Wanna see something scary?

[Linked Image]


TT, I actually saw this picture in another thread about brake performance you commented on. The funny thing is that when I reverse the bike the front brake works a lot better, it actually stops the bike.

Since my last post I have taken the brake apart again and tried to do the reassemble "by the book". This time it got even worse, now I can literally pull the brake lever all I can and then walk with the bike and nothing happens, well you can hear the noise from the brake but nothing more. Its obvious this break is extremely sensitive or have gotten very sensitive over the last 60 years. I will try to reassemble the break one more time and if it doesn't get any better I will take the parts to a break specialist and see if they can sort it out for me. Regardless, I will post my experiences back here and it will maybe help someone else.

Cheers/ Chris

Re: 8 SLS performance [Re: TrophyTR6] #718220
12/09/17 12:05 pm
12/09/17 12:05 pm
Joined: Jul 2006
Posts: 376
Kent, UK
N
Nick_Smith Offline
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N
Joined: Jul 2006
Posts: 376
Kent, UK
You still have no real idea of what percentage of the shoes is contacting the drum (and vice-versa).

I'd maybe consider 'colouring in' the braking surface on the drum with a black marker pen, and then operating the brake, to see how much of the ink is rubbed off.

In theory, the whole width of the braking surface should have all the ink cleaned off - at the worst, it will all still be there, and your brake shoes will only be contacting the 'step' where the skimming ends.
If only part of the width is cleaned off, then maybe the skimming is 'tapered', or the drum has changed shape when spoked up.

You could try similar on the shoes, with some pencil 'cross-hatchings'

I'm not sure what model bike you have, but try slacking off the main nut holding the backplate, and also the bolt holding the torque arm on the fork leg (and the fulcrum nut if there is one), and see if there is any improvement when the brake is applied.
If there is, push the machine forward, and put the brake on - hard.
This ought to centre the shoes and plate.
You can then do up the nuts and bolt (ideally with the brake still 'on' to retain the positioning).

Of course, if your brake shoes are only making minimal contact, this won't make very much difference.

Nick

Last edited by Nick_Smith; 12/09/17 12:07 pm.

"1967 TR6R"
Re: 8 SLS performance [Re: TrophyTR6] #718222
12/09/17 12:23 pm
12/09/17 12:23 pm
Joined: Jul 2012
Posts: 1,616
UK Berks
A
AngloBike Offline
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A
Joined: Jul 2012
Posts: 1,616
UK Berks
There used to be a guy at Kempton autojumbles who specialised in hydraulic brake conversions on brit bikes that weren't triumph/bsa/Norton - can't remember what marque . He isn't there nowadays but it must be possible to do a hydraulic conversion with a moderate workshop. No good if you want original though.
The brake switch inline was notorious for spongy cables

Re: 8 SLS performance [Re: TrophyTR6] #718268
12/09/17 8:46 pm
12/09/17 8:46 pm
Joined: Jun 2007
Posts: 5,854
Maui Hawaii
HawaiianTiger Offline

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HawaiianTiger  Offline

BritBike Forum member
Joined: Jun 2007
Posts: 5,854
Maui Hawaii
I once installed a TLS linkage and cams in one of these brakes. It was self servo type of brake, the harder you squeezed the lever, the harder the brake came on and a little more than you might expect. It was scary, to tell the truth. I took it off after a short while.

The backward brake lever in TT's post reminded me of it. I'd wager that one does a bit of the same action....

Cheers,
Bill


Bikes
1974 Commando
1985 Honda Nighthawk 650
1957 Thunderbird/T110 "Flying Tiger"
Antique Fans: Loads of Emersons (Two six wingers) plus gyros and orbiters.
Re: 8 SLS performance [Re: HawaiianTiger] #718275
12/09/17 9:35 pm
12/09/17 9:35 pm
Joined: Aug 2001
Posts: 7,432
scotland
triton thrasher Offline
BritBike Forum member
triton thrasher  Offline
BritBike Forum member
Joined: Aug 2001
Posts: 7,432
scotland
Originally Posted by HawaiianTiger
I once installed a TLS linkage and cams in one of these brakes. It was self servo type of brake, the harder you squeezed the lever, the harder the brake came on and a little more than you might expect. It was scary, to tell the truth.

Cheers,
Bill



People have landed themselves with too much self-servo, through drum brake experiments.


Amateur Loctite enthusiast.
Re: 8 SLS performance [Re: TrophyTR6] #718284
12/10/17 1:57 am
12/10/17 1:57 am
Joined: Apr 2007
Posts: 795
Brisbane, Australia
BrizzoBrit Offline

Life member
BrizzoBrit  Offline

Life member
Joined: Apr 2007
Posts: 795
Brisbane, Australia
There is an article circulating around called "To lead or to trail... That is the question" I only have it as a PDF so cannot reproduce it here and I dont have the web source noted. I think I got it after a forum search. May have been here or on B50.org

Anyway it discusses the cutaway of the lining. TT has got all the clues on this, but I wonder if you put the biggest cutaway (relived lining) on the trailing shoe whether this would help? It looks to me like the big cutaway is on the leading edge. This may exacerbate the effect TT is talking about I believe. But, employ the extreme caution about strong servo action mentioned above, however, if testing this.

Looking at your photos they look like lovely new linings that are made of a bonded composite material. My experience with those is that they are inferior. I even bought expensive Ferodo brand linings which were no better then the mush sold by the local guy. As an improvement on new 'bonded' linings I installed the best set of original linings I could find, even though they were worn. I finally found a local source for 'woven' linings after seeking information here. Woven linings had been recommended as being very useful. I found they transformed the rear brake potential. There's a photo in my rebuild thread http://www.britbike.com/forums/ubbt...;Main=72865&Number=693695#Post693695 Havent got to the front brake yet as the original linings are working well. But this will be happening soon.

I know several of the UK-based members used a relining service that seemingly fits woven linings (product name finishes in 'Gold?'). I think Villiers Services that Kommando mentions could be one of those. As Bill says, definitely get rid of any cable with a brake light switch. These add excess sponginess. I now get my cables custom made and they are better than many of the bike shop ones.

Ray

Last edited by BrizzoBrit; 12/10/17 2:09 am.

BSA 1969 A65F
BSA 1966 A65H
Triumph 1968 T120
Kawasaki A1R
& too many projects!
Re: 8 SLS performance [Re: TrophyTR6] #718287
12/10/17 3:49 am
12/10/17 3:49 am
Joined: Jun 2007
Posts: 5,854
Maui Hawaii
HawaiianTiger Offline

BritBike Forum member
HawaiianTiger  Offline

BritBike Forum member
Joined: Jun 2007
Posts: 5,854
Maui Hawaii
I gave up on a couple of my bikes and just laced up another wheel and bought the drum and brake from a 69-70 bike.

[Linked Image]626T06 by [url=https://www.flickr.com/photos/152305986@N08/]

I try to disguise them a bit. Most folks don't notice it until you point in out. If you don't have a disc on your Triumph, this is probably second best.

Also, the brake from the 54-56 bikes with the scoop ain't half bad.

Cheers,
Bill


Bikes
1974 Commando
1985 Honda Nighthawk 650
1957 Thunderbird/T110 "Flying Tiger"
Antique Fans: Loads of Emersons (Two six wingers) plus gyros and orbiters.
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