Drum brakes.

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Apr 20, 2011
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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 he 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 break 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 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!
 
as for the twin leading shoe front brake shoes, I purchased different brands, even the Ferodo was way under size, I believe that when they were made the manufacturer believed that the correct size was 200mm whoch is 3.2mm (1/8") under 8"
I also manufacture this brake shoe , mine is correct with minimal clearance , I've sold many to people who have complained about the same problem with other suppliers.
 
I've had the same problem, on my Bonnie both brakes are almost adjusted to the maximum, although they work quite well. I used the emery paper stuck inside the drum method to machine the shoes. Before I had maybe 30% contact area on the front shoes, after more than 90%. (Just a tip for those out there with no tools or money :mrgreen:)

Webby
 
madass140 said:
as for the twin leading shoe front brake shoes, I purchased different brands, even the Ferodo was way under size, I believe that when they were made the manufacturer believed that the correct size was 200mm whoch is 3.2mm (1/8") under 8"
I also manufacture this brake shoe , mine is correct with minimal clearance , I've sold many to people who have complained about the same problem with other suppliers.

So, where can I purchase these brake shoes in the future when I need them?
 
Webby03 said:
I've had the same problem, on my Bonnie both brakes are almost adjusted to the maximum, although they work quite well. I used the emery paper stuck inside the drum method to machine the shoes. Before I had maybe 30% contact area on the front shoes, after more than 90%. (Just a tip for those out there with no tools or money :mrgreen:)

Webby

Nothing wrong with improvising, but exactly how do you stop the emery revolving in the drum unless you glue it to the inside of the drum…..or am I missing something here :?:
 
Yeah, glue . . .

Or, assemble, ride, brake, disassemble, sand the witness marks, reassemble, ride, brake, dissassemble, sand, . . . . . and so on. Not as bad as it sounds, works well.
 
"Thanks for the reply, but can we have your location as the postage costs across the pond are now quite high."
Bernhard

you are right $20 for shipping from me to the US.
Shoes, front only $35 for my friends here.
 
madass140 said:
"Thanks for the reply, but can we have your location as the postage costs across the pond are now quite high."
Bernhard

you are right $20 for shipping from me to the US.
Shoes, front only $35 for my friends here.

Kabong-nice!
 
mikegray660 said:
madass140 said:
"Thanks for the reply, but can we have your location as the postage costs across the pond are now quite high."
Bernhard

you are right $20 for shipping from me to the US.
Shoes, front only $35 for my friends here.

Kabong-nice!


Sorry I think we have crossed wires here, I assumed that you are in the states, so, what’s the postage to the UK mainland, Please?
 
Bernhard said:
Sorry I think we have crossed wires here, I assumed that you are in the states,

If our members would only bother to include their location in their profile then it could help to avoid a lot of unnecessary confusion and uncertainty - especially where buying and selling is concerned. :roll:

To add your location to your profile:
Log in >User Control Panel(top left)>Profile = Add your location >Submit.
 
Bernhard said:
Webby03 said:
I've had the same problem, on my Bonnie both brakes are almost adjusted to the maximum, although they work quite well. I used the emery paper stuck inside the drum method to machine the shoes. Before I had maybe 30% contact area on the front shoes, after more than 90%. (Just a tip for those out there with no tools or money :mrgreen:)

Webby

Nothing wrong with improvising, but exactly how do you stop the emery revolving in the drum unless you glue it to the inside of the drum…..or am I missing something here :?:

Double sided (double faced) tape. The stuff you can buy for sticking carpets down works a treat :) Just be sure to degrease the drum before and after.

Webby
 
mikegray660 said:
Ok course rather than the shadytree brake service, you could always get it done correctly

http://www.vintagebrake.com/

RaceTech offers drum brake arcing, too. Has anybody tried them or got a comment? They are in the same town as me. I am planning to have them true the brakes on my Triumph, but it would be good to read any feedback before letting them loose on my bike.
 
I had a pair of wheels done on both a 500 Velo and a 750 Atlas by Joe Dunphy in the 1960/70s and was VERY impressed by the improved stopping power the first time.
Although it is very expensive to have done now, it would be worth it if it stops you hitting the side of a car driven by one of those “sorry, I didn’t see you” drivers.
I developed my own technique of getting better brakes with shop brought shoes.
 
The brakes on my P11 are, of course, Matchless. Rather than the steel plate formed over the end of the aluminum (aluminium?) shoe on Nortons, these shoes have a round steel insert which can be shimmed out for a tighter fit to the drum. Doing a proper shoe radius grinding is great, but it seems the only places that do it anymore are mail-order concerns.

Those that do their own brake shoes, don't forget to center the shoes in the drum (apply the brake while tightening the axle nut).
 
The main problem is that on the Norton brakes, the manufactures cut costs by supplying thinner brake lining that requires a lot of the brake adjustment to be taken up before they work, along with old bikes that have worn out brake drums.
Hence getting oversize linings fitted, then machined down to the drum size is sometimes the only way to get a good drum brake.

The old bikes also suffer from worn pivot shafts and holes that cause uneven actuation. Re-bush if necessary.
 
Hello everybody. I am looking for a 4 leading front brake with two shoe brake plates in commando style. Something like Grimeca 230 but with commado plates. Anyone noticed something like this?
 
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