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The lounge Relax, take a break from photo and camera talk - have a chat about something else for a change. Just keep it clean and polite!

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  #106  
Old 23rd January 2019
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Re: Political: Time for the little guy ?

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Originally Posted by Otto View Post
The main difference as far as I can see is the calipers are painted red! The discs are not drilled.
I think you will find the Brembo callipers have two or even four cylinders, rather than the usual single cylinder on normal production vehicles. he idea is to apply greater braking pressure over a larger area, and with less distortion of the friction pads.

Slotted or drilled disks are optional. The benefits are mainly cosmetic but they double the cost.
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  #107  
Old 23rd January 2019
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Re: Political: Time for the little guy ?

I thought the idea with slotted or drilled disks was to allow the expansion of the hot air caused by hard braking to be "absorbed" by the disk rather than producing a cushion of air between disk and brake material. The hot air dissipated as the disk turned and that part was no longer in contact with the brake material. Somewhat akin to the sipes in tyres I suppose.

I had a Citroen XM that ate brake disks and pads. My local mechanic put it down to the heavy bodyshell (dipped galvanised to prevent rust) and softer material that is used these days for the brake disk. The XM's had a foot operated parking brake and no hill start facility - but you got used to it.

My current car ate a bake pad and disk in about a week when a piece of gravel got stuck between the two! Check regularly and immediately on hearing any unusual sound.

I also use green stuff pads as they produce less brake dust and (or are meant to) give slightly better stopping power than standard pads.
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  #108  
Old 23rd January 2019
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Re: Political: Time for the little guy ?

This thread seems to have become a discussion on cars and motorcycles
Just saying
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  #109  
Old 23rd January 2019
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Re: Political: Time for the little guy ?

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Originally Posted by TimP View Post
EBC are a well known maker of pads (I know this from my days riding motorcycles)
Brake pads on a motorcycle! I used to buy drum brake linings and rivet them on - not forgetting to chamfer the leading edges.

Jim
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  #110  
Old 23rd January 2019
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Re: Political: Time for the little guy ?

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Originally Posted by OM USer View Post
I thought the idea with slotted or drilled disks was to allow the expansion of the hot air caused by hard braking to be "absorbed" by the disk rather than producing a cushion of air between disk and brake material. The hot air dissipated as the disk turned and that part was no longer in contact with the brake material. Somewhat akin to the sipes in tyres I suppose.
I'm guessing, but I would think that the slots/holes were to clear any debris or water.

Jim
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  #111  
Old 23rd January 2019
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Re: Political: Time for the little guy ?

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Brake pads on a motorcycle! I used to buy drum brake linings and rivet them on - not forgetting to chamfer the leading edges.

Jim
Yep, pads at both ends, two sets at the front and a single much smaller one at the rear!
Your memories are from a time when stopping distance was measured in minutes.
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  #112  
Old 23rd January 2019
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Re: Political: Time for the little guy ?

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Brake pads on a motorcycle! I used to buy drum brake linings and rivet them on - not forgetting to chamfer the leading edges.

Jim
Me too, and we are both still here to tell the tale.
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  #113  
Old 23rd January 2019
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Re: Political: Time for the little guy ?

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I'm guessing, but I would think that the slots/holes were to clear any debris or water.

Jim
That is the idea, but the benefit on road going vehicles is questionable.

Holes drilled in brake disks can be noisy when braking and also encourage stress cracking.
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Old 23rd January 2019
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Re: Political: Time for the little guy ?

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Originally Posted by Naughty Nigel View Post
That is the idea, but the benefit on road going vehicles is questionable.

Holes drilled in brake disks can be noisy when braking and also encourage stress cracking.
The edges of the holes should be radiused with a smooth finish. Any surface flaw is a potential nucleus of a crack. On gas turbine engines I've been involved with, a certain number of cracks were permitted between air dilution holes in the combustion chamber liner.

Jim
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Re: Political: Time for the little guy ?

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The edges of the holes should be radiused with a smooth finish. Any surface flaw is a potential nucleus of a crack. On gas turbine engines I've been involved with, a certain number of cracks were permitted between air dilution holes in the combustion chamber liner.

Jim
That is correct. However, I know of several people, admittedly racing motorcyclists, who had problems with cast iron or stainless steel brake disks either cracking, or in one case breaking altogether owing to stress originating at holes.

Brake disks are obviously subject to a lot of mechanical stress, plus the thermal stresses caused by sudden heating and cooling, which in extreme cases also affects temper.
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