Loose paddles rear brake drum

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Stuffa

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I pulled my rear wheel off because the drum was rubbing on one spot when spinning the wheel. The paddles on the brake drum had been welded but the welds are a bit bodgy and have let go on two of the paddles and they are loose. You could see on the welds that the shoes had been rubbing on the welds. Can these be welded again someway or should so be looking at getting a new drum.
 
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I say get a new one. Can't tell for sure from the picture but to me the teeth on the sprocket portion look worn out.
 
I agree with the old beezer. Who wants to worry about their wheels falling apart?
 
The rear wheel parts drawing shows part #21 as Washer, Flat, Brake Plate Packing used As Required (AR).
This washer (it is just a thin shim) spaces the brake plate from the sprocket.
This spacer, when originally installed, is easy to lose or misidentify when rebuilding the rear brake.
It definitely can cure the slight scraping I think you are describing.
 
the scraping can be caused by a warped brake plate, I've straightened heaps of them
 
I removed some loose ones to check how they are fitted, they are actually threaded and then riveted, an abortion of
an idea, no wonder they work loose. A better cush drive arrangement is a good idea.
 
Bob Z. said:
The rear wheel parts drawing shows part #21 as Washer, Flat, Brake Plate Packing used As Required (AR).
This washer (it is just a thin shim) spaces the brake plate from the sprocket.
This spacer, when originally installed, is easy to lose or misidentify when rebuilding the rear brake.
It definitely can cure the slight scraping I think you are describing.
Click to expand...
Thanks mate but the washer was in place
 
madass140 said:
the scraping can be caused by a warped brake plate, I've straightened heaps of them
Click to expand...
madass140 said:
I removed some loose ones to check how they are fitted, they are actually threaded and then riveted, an abortion of
an idea, no wonder they work loose. A better cush drive arrangement is a good idea.
Click to expand...
Are there better options out there? I agree it needs replacing. The nuts that hold the brake shoes on have been rubbing on the welds. Also I knocked the bearing out and it needs replacing.
 
the brake plate needs to be fitted solidly on a mandrel thru the axle hole and rotated in a lathe , old lathe preferably,
and corrected via some good wallops with a suitable hammer.
Sounds like you would be replacing the sprocket drum then of course you would be fitting a new bearing anyway.
Remember when you get it all back together you still end up with the poor design you started with.
 
Do you ever fit more than the one #21 spacing washer?Mine does not rub anywhere but the brake is useless.It should lock the wheel when stomping on it?
Mine will just hold the bike in place on an incline.New bearings,shoes,etc.Everything running true.It just seems like a 1/4" of the shoes are in contact with the drum.What else is there to check?
Thanks
 
You need a new sprocket from that Photo , yes. Also the double row bearing gets very neglected over the years from lack of fresh grease . I've seen welds and rivets to hold in those paddles according to the year model and they should always be checked for safety sake.
 
YING said:
Do you ever fit more than the one #21 spacing washer?Mine does not rub anywhere but the brake is useless.It should lock the wheel when stomping on it?
Mine will just hold the bike in place on an incline.New bearings,shoes,etc.Everything running true.It just seems like a 1/4" of the shoes are in contact with the drum.What else is there to check?
Thanks
Click to expand...

Send that drum and backing plate to https://www.vintagebrake.com/ and you’ll get back a wonderfully progressive stopper.
 
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I had the brake shoe nuts wear on the drum because the drum bearing moved as the circlip was not seated. So could be bearing wear.

In my situation the chain guard also had damage. I bought my drum from Norvil and the circlip slot was too tight so I had to thin the circlip on an oilstone.
 
HoveToo said:
I had the brake shoe nuts wear on the drum because the drum bearing moved as the circlip was not seated. So could be bearing wear.

In my situation the chain guard also had damage. I bought my drum from Norvil and the circlip slot was too tight so I had to thin the circlip on an oilstone.
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Hmm. drum bearing moved? Its a press fit. Actually they are one of the hardest bearings to remove on a Commando.
 
The circlip was not located in the groove so the bearing was free to move as I tightened up the axle. It happened twice so I checked the circlip fit and discovered that was too thick for the slot and I had to thin it to ensure it bedded in correctly. The visible symptoms were the drag of the chain against the guard, and the brake shoes and the retaining bolts rubbing against the rear face of the drum.
 
The double row bearing circlip is indeed another issue. The slot for it can be too tight or too loose depending on who supplies the new hub / brake/ sprocket and the year of that. The circlip has been known to pop out.
 
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