Unable to adjust front drum brake

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beast

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Hi All

Quite new to this forum and English is not my native language. I have a 69 Commando with front drum brakes that I am refurbishing. The drums where in a very bad shape because of rust that made grooves and have been grinded in a rotating mill to get an even surface (do not know the correct words here).
I have the stiffening kit mounted and my main problem now is that I am almost unable to adjust the brakes unless all adjustment is all the way out (at drum and hand lever). I can foresee that in a short while I will be unable to adjust it correctly because of shoe wear. What can I do here - other shoes or cable?

Thank you in advance.
Benny
 
Get your shoes relined by someone who will custom make the lining to the right thickness so your adjustment goes back to factory original.

There are 2 suppliers in the UK, not much to choose between them, both are good.

Villiers Services

Villiers Services : - Tools / Workshop Accessories Villiers Parts Motorcycles for sale General motorcycle spares Oils / Paint / Consumables Diecast Models Brake Shoe Re-Lining Service Gift Vouchers Trials Parts Amc Two Stroke (James/ Barnett) Greeves Spares Helmets / Clothes etc ecommerce, open...
villiersservices.co.uk villiersservices.co.uk

For any motorcycle shoes we charge £21.95 a pair inclusive of vat and postage is free! Please email or call for a quote on car, trailer, truck shoes or industrial clutches.

We re-Line the shoes to their original width, if you require under or oversize linings, please let us know on your note with the shoes. To measure and exact size, all you need to do is measure the inside diameter of the hub and the outside diameter of the shoes on the back plate (excluding the current linings) write those sizes down with your letter and we will do the rest.

Vintage and Classic Brake and Clutch Relining – Saftek

saftek.co.uk saftek.co.uk

Oversized thickness linings and drum skimming are available.
 
You need to be careful with the angle of the cams when the brake is hard on. If there is too much angle, the brake can become dangerous. You need to make sure the fit of the shoes in the drum requires minimum slack to be taken up when adjusting. In other words, run the linings as close as possible to the drum without getting drag. In the old days some brake services used to cater for motorcycle racers. They would fit the shoes to the drum correctly.
 
You mean they would fit oversized brake linnings onto the shoes then fit a 0.020 inch shim onto the flats of the shoes, then skim down on a mandrel on a lathe to the EXACT brake drum diameter before removing the shims. Then file a 30 degrees angle on the leading edge of the brake linnings to prevent "Bite"
 
As has been posted already, the shoes do need to be the right thickness to work properly. Do not just keep adjusting out the slack forever, when you do that you can reach a point with worn shoes whereby the brake operating cams will go ‘over centre’ when yanked on really hard. When this happens the brake stays locked on full.
 
I've put in one previous post about making your own slippers, look up & search my posts afew years ago.
 
Packing the cam is dangerous. Much better to machine the linings to fit the drum. But do not forget to cut the leading edge of the linings back on an angle. If the leading edge heats up it can become sticky and cause the brake to lock, and launch you if you hold it on too long. The first time I raced, I stepped off at about 90 MPH. The bike was never going to stop, but then it did.
 
beast said:
I do not understand this?
Click to expand...
The two brake levers fit on square pegs...the brake cams. You can pull them off the square pegs, flip them over, and they will give you a slightly different position...perhaps to your advantage. It would be good to follow the above suggestions first.
 
seattle##gs said:
The two brake levers fit on square pegs...the brake cams. You can pull them off the square pegs, flip them over, and they will give you a slightly different position...perhaps to your advantage. It would be good to follow the above suggestions first.
Click to expand...
If it needs that much movement then I would refer the OP to post #12... it’s dangerous.
 
acotrel said:
Packing the cam is dangerous. Much better to machine the linings to fit the drum. But do not forget to cut the leading edge of the linings back on an angle. If the leading edge heats up it can become sticky and cause the brake to lock, and launch you if you hold it on too long. The first time I raced, I stepped off at about 90 MPH. The bike was never going to stop, but then it did.
Click to expand...
Yes acotrel, you are so good with drum brakes you should come with a Government Health warning !
 
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I think there's a problem with some of the supplier's lengths of brake cables. I bought two from RGM (one as a spare) and the outer seems too short.
I bought the cable without the brake light switch, as I don't have one.
I artificially extended the length of it by placing a spiggoted ferrule into the adjuster at the drum end.
What's the "proper" measurement of free play for a front brake cable?

20210424_070546.jpg
 
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Or, if the inner cable is to long, and you are 100% sure the brake linnings are just kissing the brake drum, without any brake on, lob off the brake nipple and shorten the cable to suit and resolder it back on taking great care to preen the inner cable over before soldering.
 
Bernhard said:
Or, if the inner cable is to long, and you are 100% sure the brake linnings are just kissing the brake drum, without any brake on, lob off the brake nipple and shorten the cable to suit and resolder it back on taking great care to preen the inner cable over before soldering.
Click to expand...
I've never been keen to alter brake cables, throttle cables yes. I'd always have a nagging doubt I'd put too much heat into the cables when soldering.
 
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