Converting old style TLS to newer support plate type

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Hortons Norton

Hortons Norton

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I'm looking at upgrading the TLS front brake with the added support plate and discovered I will need to replace both cams and also the pivot shafts. It looks as if I will need to drill out the one fixed pivot, is it as easy as that? Just wondering if the new pivot from the one removed will fit in the boss? And also those that have done this how much of a difference did it make? Thanks for your replys, Chuck.
 
Just what I needed, as always your an awesome source of information, or where to find it. Thanks a million. Chuck.
 
"They" say, it really is important to bush the axle hole through the brake plate. The forces on the brakes tend to torque the plate so it becomes hourglass shaped. Therefore loose, I wish I had a lathe guy nearby to make that bushing for me.... and bore the hole as needed.
 
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When I read the above link L.A.B. sent it does say that, Old Britt's a has a service to do just that. Don't suppose anyone makes just those?
 
All I did was arc new shoes to the drum (easy), make sure the TLS adjuster was properly adjusted, tightened the axle with the brakes tight, and ended up with about 90% contact and it made the brake perfectly acceptable and about 90% better than before. Of course it won't cure the heat issue with too much braking, neither will the plate. I'm not sure the extra plate is worth the money, but maybe for some.
 
This aft. I flipped the brake actuating levers over to get a better angle and it made an improvement. I used the better of the two angles and also had to flop the top one. Easy enough to do. And free. If you are handy with a milling machine you could make the lever sit in any position you wanted. It would take a piece of one inch stock 1/4" wide, using a 3/8 end mill to mill the slot. My test ride was not very long as it was cold and dark.
 
Another biggie is to get rid of that sponge for a front brake light switch if you still have that. Lots of articles on using a micro-switch in different places, wouldn't be hard to implement. Notice that those front shoes also have 'pads' or 'shoes' on the ends, sometimes they're missing which makes for a longer actuation. I actually had to take them off to arc my shoes. I put them back on when I finished.
 
Hortons Norton said:
I'm looking at upgrading the TLS front brake with the added support plate and discovered I will need to replace both cams and also the pivot shafts. It looks as if I will need to drill out the one fixed pivot, is it as easy as that? Just wondering if the new pivot from the one removed will fit in the boss? And also those that have done this how much of a difference did it make? Thanks for your replys, Chuck.
Click to expand...

I installed one of these plates on my '71 and it made no difference. I suspect turning the drum, arcing the brake shoes, using Ferodo shoes, and installing a new brake cable would be a much better investment (or just send the whole lot off to Vintage Brake). I think the plate adds friction to the movement of the cams too.
 
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I was willing to try the arcing, new shoes, adjusting the adjuster and centering the axle as a start. I was not disappointed. I really can't imagine the plate would do that much, shoot as soon as the shoes hit the drum, they start to self center. Now I didn't try a new cable and getting rid of the sponge, but I imagine they would help. Plus it didn't cost that much since I wanted new shoes anyhow and how much does a piece of #80 grit sandpaper cost. I spent about 2 hours doing the whole job, including cleanup. Plus you get to bond with the Norton, Vintage won't do that.

The one thing I was disappointed with was trying to rebuild my Amals. It cost me as much to get new parts, sleeve the slides and all the work when I could have bought a set of premiers for the same price and maybe just installed them. One never knows.

Long story short, try the simple stuff first, unless there's money to burn or time constraints.
 
I installed the stiffening kit on three bikes. Absolutely essential. The issue with the original TLS is that the cams deflect when they push the shoes against the drum so they can never create high breaking force. The stiffening kit creates a counter bearing for the cams so the deflection is eliminated and the full force goes against the shoe.

I followed the instructions for improving the break: https://www.oldbritts.com/f_drum_upgrade.html

With all these upgrades and proper adjustment, breaking is now better than a stock Commando disc and maybe close to a Commando disc break with a sleeved cylinder which I have on my 850. In the end its still a drum break though.
 
DogT said:
i Notice that those front shoes also have 'pads' or 'shoes' on the ends, sometimes they're missing which makes for a longer actuation. I actually had to take them off to arc my shoes. I put them back on when I finished.
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Wrong thing to do but if you are doing this as a home made job in your shed then needs must. The shoes will wear down to the diameter of the drum eventually so it all helps. I posted on this website a few years ago how I did this job at home I'll have to look it up and post it here.
 
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If you can get a drum brake working good enough to race with, it is usually too dangerous. TAKE CARE ! - A disc brake is a much better option and probably cheaper in the long run.
 
DogT said:
Another biggie is to get rid of that sponge for a front brake light switch if you still have that. Lots of articles on using a micro-switch in different places, wouldn't be hard to implement. Notice that those front shoes also have 'pads' or 'shoes' on the ends, sometimes they're missing which makes for a longer actuation. I actually had to take them off to arc my shoes. I put them back on when I finished.
Click to expand...
I have installed a Magura mini (normally open) switch on both my featherbed bikes in order to:
1. ensure the brake light comes on for the front brake (early bikes didn't!)
2. Get rid of the sponginess associated with the early commando switch (mid-cable)
Here's a couple of shots - works well. If anyone wants details on the parts, let me know
All done with hacksaw, files, drill and taps.
Cheers
Rob
Converting old style TLS to newer support plate type
Converting old style TLS to newer support plate type
Converting old style TLS to newer support plate type
 
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The Magura normally open micro switch is available from Venhill Engineering part No 0128496 and priced at £10.30.... recently purchased one myself for the Magura master cylinder i purchased from them:)
 
As I said I previously posted on how you can do homemade improvements to any drum brake;

https://www.accessnorton.com/NortonCommando/drum-brakes.10690/

I have found that most new brake shoes fall far short of perfection as when assembled there is usually a wide gap between the shoes and the drum, I have to take up a considerable amount of the brake adjusters before I get contact, unless you have oversize shoes fitted, which are then skimmed down to fit the drum.

My method merely involved getting the shoes closer to the drum by using metal spaces slightly less the width of the flats that are bent over in both corners on the flat part of the brake shoes which kisses the pivot flats of the 2ls drum. If you have a single LS you need to make a pair, if 2ls you need to make 4 of them.

Note; don’t use any metal more than ½ the thickness of the linings or the metal spaces will hit he drum!! Aim to get the shoes within about .020 or more closer to the brake drum when running freely. …… If you have a lathe you can skim the linings mounted on the brake plate, by first fitting a .020 spacer under each of the flats, then turning down tho the exact diameter of the brake drum….. then remove all the .020 spacers.

If you don’t have a lathe don’t worry, you will have a much better brake when you pull the lever, as even more of the shoe will be in contact when the brake beds in.

Also, don’t forget to file a shallow 30 angle on the leading edges of the shoe linings or the brake will grab.

If the drum is so worn that the metal spaces cannot compensate, you will have to weld even more flat metal onto all the spaces to compensate. At one time I could buy these spaces from my local motorcycle emporium.

NOTE!!! Disclaimer; Asbestos Brake dust is very harmful when machined and I will not be held responsible for any brake shoe work carried out, so always wear a dust mask!
 
If you cut the leading edges of the linings back to stop the brake from grabbing, you can still find yourself picking your body up of the road, when the mod has not been effective. If I had to not raced for 12 years using a drum brake, I would have continued racing regularly beyond 1973. Drum brakes are simply not worth it. A disc is cheaper and safer. - At least you can grab a handful without shitting yourself. I'm not kidding - drum front brakes should be banned. Even with a road bike, you can end up under a truck if the brake brings you down.

When I was racing, there was a company in Melbourne, which would turn the linings to fit the drum and supply any compound you wanted. I've had brakes which would not work until heated up, others which were savage when cold, and some which were mediocre for whole races. Which would you prefer ? - With discs, you get none of that. I had a savage bike and unreliable brakes. - AND ANXIETY !

With my Seeley 850, I have dual discs, two Lockheed callipers - it is one finger operation and it STOPS !
 
Bernhard said:
As I said I previously posted on how you can do homemade improvements to any drum brake;

https://www.accessnorton.com/NortonCommando/drum-brakes.10690/

I have found that most new brake shoes fall far short of perfection as when assembled there is usually a wide gap between the shoes and the drum, I have to take up a considerable amount of the brake adjusters before I get contact, unless you have oversize shoes fitted, which are then skimmed down to fit the drum.

My method merely involved getting the shoes closer to the drum by using metal spaces slightly less the width of the flats that are bent over in both corners on the flat part of the brake shoes which kisses the pivot flats of the 2ls drum. If you have a single LS you need to make a pair, if 2ls you need to make 4 of them.

Note; don’t use any metal more than ½ the thickness of the linings or the metal spaces will hit he drum!! Aim to get the shoes within about .020 or more closer to the brake drum when running freely. …… If you have a lathe you can skim the linings mounted on the brake plate, by first fitting a .020 spacer under each of the flats, then turning down tho the exact diameter of the brake drum….. then remove all the .020 spacers.

If you don’t have a lathe don’t worry, you will have a much better brake when you pull the lever, as even more of the shoe will be in contact when the brake beds in.

Also, don’t forget to file a shallow 30 angle on the leading edges of the shoe linings or the brake will grab.

If the drum is so worn that the metal spaces cannot compensate, you will have to weld even more flat metal onto all the spaces to compensate. At one time I could buy these spaces from my local motorcycle emporium.

NOTE!!! Disclaimer; Asbestos Brake dust is very harmful when machined and I will not be held responsible for any brake shoe work carried out, so always wear a dust mask!
Click to expand...

I would never machine asbestos, even wearing a dust mask. If you do it at home, what happens to the material which is turned off the bits you machine ? Brake shops usually have properly engineered removal systems to collect the dust. With disc brakes, you just change the pads.
 
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