Author Topic: Which Brake Size?  (Read 253 times)

Offline LynnLegend

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Which Brake Size?
« on: 10.04. 2020 15:54 »
Hi all,

Front brake on my 59 A7 is useless, I have taken it to pieces (photos attached if they are of any use) and intend to replace the shoes to see if that improves things.

I wanted to double check that I definitely want the 7 inch shoes - I’m not particularly mechanically minded, but it seems simple enough.

I have found these on eBay:

https://www.ebay.co.uk/itm/161350683800


Furthermore, is there anything else I should do while I’m messing about with it? The inside of the hub (where the shoes press against) is smooth as a baby’s bottom - should there be some level of abrasion there too?

Any help or guidance would be hugely appreciated.

Thanks,

Sam.
'59 A7 - No idea what I'm doing with it.

Online Billybream

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Re: Which Brake Size?
« Reply #1 on: 10.04. 2020 16:35 »
You have cast iron 8" full width hub,  the Ebay shoes are not suitable. Looks to be water ingress, causing rust so hub needs good clean, springs look rough.
Under normal circumstances, but our challenging times may not permit this, I would have your existing shoes relined, Saftex is recommended.
The front brake will never be brilliant, hence why so many owners convert to TLS arrangement
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Online Triton Thrasher

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Re: Which Brake Size?
« Reply #2 on: 10.04. 2020 18:56 »
You have cast iron 8" full width hub,  the Ebay shoes are not suitable. Looks to be water ingress, causing rust so hub needs good clean, springs look rough.
Under normal circumstances, but our challenging times may not permit this, I would have your existing shoes relined, Saftex is recommended.
The front brake will never be brilliant, hence why so many owners convert to TLS arrangement

Do you mean Saftek?

https://saftek.co.uk/friction-products-for-classic-vehicles-and-race-applications/

Online RDfella

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Re: Which Brake Size?
« Reply #3 on: 10.04. 2020 19:29 »
Don't those FWH 's come in 7" and 8"? Not sure, but either way they're useless. I, like many others, have found the single-sided 8" far superior in stopping power. Dunno why an 8" SS should be so much better than an 8" FWH but, as Harry Worth used to say 'there it is'.
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Online JulianS

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Re: Which Brake Size?
« Reply #4 on: 10.04. 2020 19:46 »
The brake looks like a 7 inch. Same as fitted to the much lighter B40 so it struggles with the weight fo an A7.

The ebay shoes are for a 7 inch half width hub, they dont fit the full width.

I suggest a careful check for damage of the shoes fitted, there seems to be a bit broken from the cam end of the shoe.

Offline LynnLegend

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Re: Which Brake Size?
« Reply #5 on: 11.04. 2020 10:19 »
Excellent, thanks all for your comments.
'59 A7 - No idea what I'm doing with it.

Online KiwiGF

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Re: Which Brake Size?
« Reply #6 on: 11.04. 2020 11:56 »
Excellent, thanks all for your comments.

There are quite a few things you can try before getting new shoes, a key thing is to get the leading shoe to contact the drum BEFORE the trailing shoe.

It’s difficult to say for sure but it does not look like the shoes are contacting the drum over the whole length, could you take more pics to show this either way?
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Offline Swarfcut

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Re: Which Brake Size?
« Reply #7 on: 11.04. 2020 20:13 »
 Sam Legend...   The leading shoe is the one which " leads" from the cam to the pivot, in other words as the wheel rotates it passes the cam first, then the pivot. Check the shoes, if they are identical, put the thickest lining in this position, an easy way to implement Kiwi's suggestion.

 Holding your breath and sanding the linings lightly to remove any glaze will improve the friction properties of the lining, as will making sure the pivot and cam are lubricated to ensure the shoes move easily. A good drum will be smooth, unmarked  truly round. An oval drum can be felt on the lever, and braking is in a series of grabs.

 The pivot may be in a slotted hole, so check if the backplate allows any chance to adjust the the pivot position. Trick here is to loosen the pivot nut and see if the pivot will move in a slot.  Reassemble  and apply the brake  hard, the shoes will centre themselves and then with the brake still on, nip up the pivot nut. This depends on the backplate you have, worst case is a fixed location.

 Operating lever should approach, but never pass the magic 90 degrees with the cable. There may be some adjustment on the cam/lever, depends on type. Some have fine splines, easy to adjust, earlier levers are a steel pressing, try turning it over to alter the angle.

 Cable...any stretch in the outer is lost braking efficiency...your effort is wasted pulling the outer cable coils together, not applying braking effort.

 The eBay shoes fit plunger A's rear and early S/A rear, not your 8" front.

Swarfy.

 

Offline LynnLegend

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Re: Which Brake Size?
« Reply #8 on: 15.04. 2020 16:41 »
Thanks once again, I will have a play tomorrow!
'59 A7 - No idea what I'm doing with it.