Author Topic: New Brake shoes to tight in the drum  (Read 14224 times)

Offline Duncan R

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New Brake shoes to tight in the drum
« on: 30.07. 2012 14:45 »
Just been sorting the rear hub out - new bearings and everything cleaned up, I bought some new Ferodo shoes  as the old ones are starting to hit the rivets(almost). Problem I have now is the new shoes are just to tight in the drum. The drum is in fair condition, is it best to remove lining material so they are free in the drum? or get the drum skimmed so the shoes fit? I thought the shoes may be a lose fit as I don't know the age or the mileage of the drum(I suspect it it is pretty old) I don't want to attempt reducing the shoes by hand as this could muck up the profile. Anyone know who could do this in the Kent?SE London area? Its a QD Hub by the way.

Many thanks

Duncan
Anglo - Indian A7SS (Actually is a 650)
Kawasaki ZZR 1100
BMW R80GS
BMW R1100GS

beezermacc

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Re: New Brake shoes to tight in the drum
« Reply #1 on: 30.07. 2012 16:35 »
I wouldn't skim the drum unless it is out of round. Removing metal will make it prone to distortion when hot. Before skimming and/or rubbing I would check the shoes loose in the drum, measure the gaps and compare the gaps with the thickness of the cam and the locating fulcrum. I have found some shoes are not very well made; if they're not of the fully floating type the position of the slot for the fulcrum may be holding the shoes slightly off centre. Three things you might try....1) check that the fulcrum slot on the shoes is a good fit on the fulcrum pin, sometimes the hole on the shoes is smaller than the diameter of the pin so the shoes don't drop all the way onto the pin - you can also widen (not deepen) the slots to enable the shoes to 'float' slightly and centralise themselves in the drum. 2) shave a bit off the foot of the brake shoes so they sit lower on the cam...... 2) Tape some medium grit sandpaper to the inside of the drum and give your shoes a light rub using the inside of the drum with the sandpaper to maintain the profile.

Offline Duncan R

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Re: New Brake shoes to tight in the drum
« Reply #2 on: 30.07. 2012 17:09 »
Hi Beezermacc,

Shoes came from C & D Autos, never had any problems with their parts before,the linings are Ferodo. There is no clearence between shoes and drum, I had to tap them in with a mallet, there is no way the hub will turn,prob needs .5mm taken off each lining.

I have just found a website for Hoppy Bikes in East London, spoke to Dave and he said drop in and he will have a look, they prepare drum brakes and linings on classics. I am going up there on Thursday.

Thanks

Duncan
Anglo - Indian A7SS (Actually is a 650)
Kawasaki ZZR 1100
BMW R80GS
BMW R1100GS

Online bsa-bill

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Re: New Brake shoes to tight in the drum
« Reply #3 on: 30.07. 2012 18:49 »
Hi Duncan
What bike did you order the shoes for, are they for the full width cast hub?
I ask because my rear hub might be worn (although it measures about right at 7"), I bought new shoes (Ermo or Ergo) but they are no better than what was in, the brake arm moves far too far before anything happens, so maybe the kind of shoes you have would work in my hub.
I'll order a set from C&D if your bike has the same hub as mine
Many thanks - Bill
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

beezermacc

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Re: New Brake shoes to tight in the drum
« Reply #4 on: 30.07. 2012 22:18 »
Hi BSA-Bill, I think you mean EMGO? (blue and yellow box?)

beezermacc

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Re: New Brake shoes to tight in the drum
« Reply #5 on: 30.07. 2012 22:23 »
Duncan, presumably you still have the old shoes so you can make a comparison. I would remove the cam and pin from the brake plate (without the brake plate you can see what is happening) and slide all the old components into the drum (linings, cam and pin) then substitute the new linings to see what is making the difference.

Offline Duncan R

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Re: New Brake shoes to tight in the drum
« Reply #6 on: 31.07. 2012 07:44 »
Hi Bill,

I ordered for 1/2 width hub QD type. I was surprised when he said they were Ferodo as I thought you could only buy Ferodo linings these days. I might give C & D a ring and see what they say. The lining material looks great.

Thanks Beezermacc, I will try that, I suppose the cam may have been built up at some stage and could be oversize I noticed a rough bit bronze or brass splatter on the side.
Anglo - Indian A7SS (Actually is a 650)
Kawasaki ZZR 1100
BMW R80GS
BMW R1100GS

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Re: New Brake shoes to tight in the drum
« Reply #7 on: 31.07. 2012 10:07 »
Quote
Hi BSA-Bill, I think you mean EMGO? (blue and yellow box?)
cheers  beezermacc those are the ones

Thanks for the info Duncan - anybody know if hey would fit full width hubs ?
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline Duncan R

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Re: New Brake shoes to tight in the drum
« Reply #8 on: 31.07. 2012 17:54 »

Bill, I am sure C & D would have the correct shoes for your hub, maybe worth giving them a call.

I am now suspecting the bike is fitted with the wrong brake cam and previous shoes were relined to suit the cam. I have dropped the shoes in with them connected to the fulcrum pin but not the cam, their is plenty of space. I will have a measure tomorrow and see if its possible to grind the cam down a bit, it prob only needs a 1mm max.

There is a fair length of exposed shaft showing when the cam is fitted in the brake plate (like its too long) this is covered up by a length of chrome tube to cover it up. Maybe the cam was off another BSA model. Anyone got a photo of rear brake set up on the Gold star type QD hub?

Many thanks

Duncan
Anglo - Indian A7SS (Actually is a 650)
Kawasaki ZZR 1100
BMW R80GS
BMW R1100GS

Offline Tumbleweed

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Re: New Brake shoes to tight in the drum
« Reply #9 on: 31.07. 2012 20:09 »
make sure any linings you shave off are asbestos free ,some really old stock arent.
Semper in excretia sumus solum profundum veriat.

Online orabanda

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Re: New Brake shoes to tight in the drum
« Reply #10 on: 31.07. 2012 23:11 »
I agree strongly with Tumbleweed; asbestos fibres WILL kill you in the cruellest way.

The fibres are so small they are hard to see; don't be complacent or casual with such a dangerous (lethal) material.

If you cannot avoid contact with asbestos linings, invest in a quality breathing mask with filters designed to cope with asbestos.

Keep your loved ones out of the shed or area; the tragedy of your child wasting away thirty years down the track is too terrible to contemplate.

Richard




Offline Duncan R

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Re: New Brake shoes to tight in the drum
« Reply #11 on: 01.08. 2012 02:38 »
Thanks,they are new not NOS. I am going to grind the cam and no
t the linings.
Anglo - Indian A7SS (Actually is a 650)
Kawasaki ZZR 1100
BMW R80GS
BMW R1100GS