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Is the backing plate really necessary?

  • Yes! It is important for the safe function and reduction of noise of the brakes.

    Votes: 10 31.3%
  • No. It is important only for the reduction of noise, but keep them around just in case.

    Votes: 12 37.5%
  • Who cares! Throw them away.

    Votes: 4 12.5%
  • Huh?

    Votes: 6 18.8%
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Discussion Starter #1


Is the backing plate really necessary?

I'm trying to install Hawk HT10 and there is no way I can fit the pads in with the backing plate. The piston is fully retracted. The pads will go in w/o the backing plate.
 

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Or you could just grind some of the pad surface...

I would imagine the backing plate keps the pistons from crushing the pad. There is an extreme amount of force placed on the backing plate.
 

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Also for heat transfer (to prevent some of it) to the piston... and noise suppression.

How about leave them off, bed them in gently, then you should have room to put them back?
 

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What you are referring to is not a backing plate, but a shim. as you are already aware of its purpose is for noise reduction. They are not necessary for proper braking (the steel BACKING PLATE protects the pad material from being crushed by distributing the load).

It has no other function. I had to work to get my Pagid Blues to fit with the shims. but its worth it to me (less noise in the long run.) I also put brake goo between the backing plate and the shim, and where the shim contacts the caliper/piston.
 

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IIRC, hawk makes these in two thicknesses. the thicker is a Viper part, not for Lotus.

I used the latter and it fit w/o interference. I don't know, but ensure you have the correct pads and that the piston is bottomed???
 

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I vote just mill a little friction material off the pads so they will fit normally, but then again I own a milling machine so that is a 5 minute project. Who needs to listen to a bunch of racket from their brakes with the shims missing? :shrug:
 

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My OEM front brakes just had a thin film bonded to the front pads (no shims), nothing on the rear pads. On my first pad change, I used this: <a href=http://www.crcindustries.com/auto/content/prod_detail.aspx?PN=05016&S=N>CRC Brake Quiet</a>. You apply it in a thin film to the backing plate, let it dry before installing the pads, and it's supposed to reduce brake squeal.

Under certain circumstances, the brakes still squealed... I think it's more important to lubricate the contact points between the backing plate and the pistons/caliper guides than to have a shim or film... I use this: <a href=http://www.crcindustries.com/auto/content/prod_detail.aspx?PN=05351&S=N>Brake Caliper Grease</a>. Apply "liberally" (especially you, Gil ;)), but make sure not to get any on the rotor or the pad's friction material.

EDIT: I just installed Hawk HT-10s a few days ago... the pads didn't look like the ones in your photo (and they had that annoying dimple on the backing plate: http://www.lotustalk.com/forums/f91/question-those-who-have-put-hawk-ht-10-a-73089/).
 

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What you are referring to is not a backing plate, but a shim. as you are already aware of its purpose is for noise reduction. They are not necessary for proper braking (the steel BACKING PLATE protects the pad material from being crushed by distributing the load).

It has no other function. I had to work to get my Pagid Blues to fit with the shims. but its worth it to me (less noise in the long run.) I also put brake goo between the backing plate and the shim, and where the shim contacts the caliper/piston.
+1

The shim is for noise reduction. The only way the shim would make an appreciable difference in keeping heat from the piston would be if it was made from stainless, or better yet titanium. If it came with your brake pads I highly doubt it is either.
 

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I'm surprised that no one has pointed out that the car will be lighter without them ;)
 

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+1

The shim is for noise reduction. The only way the shim would make an appreciable difference in keeping heat from the piston would be if it was made from stainless, or better yet titanium. If it came with your brake pads I highly doubt it is either.
Actually, heat transfer would be reduced because the contact between the shim and backing plate is minimal through the paint and the adhesive. The changes in material affect thermal contact conductance.

Yes, it calls to mind why an insulating shim needs to be of any specific material; the simply fact that there is a shim is half the improvement....
 

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Actually, heat transfer would be reduced because the contact between the shim and backing plate is minimal through the paint and the adhesive. The changes in material affect thermal contact conductance.

Yes, it calls to mind why an insulating shim needs to be of any specific material; the simply fact that there is a shim is half the improvement....

No shim < any shim < stainless shim < titanium shim as far as heat transfer goes.
 

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Discussion Starter #12
My photo above was for illustrative purposes. My HT10 actually had an annoying ZIT-looking thing sticking out that I had to file down.

My OEM front brakes had a "thin film" but if you stick a small screwdriver in it, it pops up and it's actually a shim. I re-used it on Pagids, and now I'm trying to reuse the shim on the HT10s and put Blue Permatex in-between, but it will not work.


My OEM front brakes just had a thin film bonded to the front pads (no shims), nothing on the rear pads. On my first pad change, I used this: <a href=http://www.crcindustries.com/auto/content/prod_detail.aspx?PN=05016&S=N>CRC Brake Quiet</a>. You apply it in a thin film to the backing plate, let it dry before installing the pads, and it's supposed to reduce brake squeal.

Under certain circumstances, the brakes still squealed... I think it's more important to lubricate the contact points between the backing plate and the pistons/caliper guides than to have a shim or film... I use this: <a href=http://www.crcindustries.com/auto/content/prod_detail.aspx?PN=05351&S=N>Brake Caliper Grease</a>. Apply "liberally" (especially you, Gil ;)), but make sure not to get any on the rotor or the pad's friction material.

EDIT: I just installed Hawk HT-10s a few days ago... the pads didn't look like the ones in your photo (and they had that annoying dimple on the backing plate: http://www.lotustalk.com/forums/f91/question-those-who-have-put-hawk-ht-10-a-73089/).
 

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My photo above was for illustrative purposes. My HT10 actually had an annoying ZIT-looking thing sticking out that I had to file down.

My OEM front brakes had a "thin film" but if you stick a small screwdriver in it, it pops up and it's actually a shim. I re-used it on Pagids, and now I'm trying to reuse the shim on the HT10s and put Blue Permatex in-between, but it will not work.
rotfl

I just dug out my OEM pads, and sure enough that thin film <b>is</b> the shim... I didn't try to pry it off at the time since it seemed to be very tenaciously bonded on. Maybe I'll try to pry them off and slip them onto the HT-10s...
 

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Discussion Starter #15
rotfl

I just dug out my OEM pads, and sure enough that thin film <b>is</b> the shim... I didn't try to pry it off at the time since it seemed to be very tenaciously bonded on. Maybe I'll try to pry them off and slip them onto the HT-10s...
Okay, so here's an update. I'm running the HT10s w/o the shims to wear it down a little so that I can slip the shim in later on. Hopefully, I can do this soon, because the brakes squeaks like a :no: at low speeds light braking. :sad:
 

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Okay, so here's an update. I'm running the HT10s w/o the shims to wear it down a little so that I can slip the shim in later on. Hopefully, I can do this soon, because the brakes squeaks like a :no: at low speeds light braking. :sad:
rotfl

I just peeled the shims off the OEM backing plates and slipped them in behind the HT10s (fronts only). I only drove about 100 miles on the new pads, and it wasn't very difficult to slip the shims in. Just use the pads as a "lever" to push back the pistons, put some brake caliper grease on the shims, and you'll be good.

I only driven 10 miles with the shims in... and the brakes seem quieter...
 

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Just a bit of an update...

Yesterday I put in a new set of HT-10s... after filing off the "dimple", I had no problem installing the new pads with the OEM shim plates... they dropped right in, without having to wear the front pads down at all.

On slightly different subject... is anyone able to change the rear pads without removing the calipers if you have both wheel studs and a two-piece rotor? Seems there's no way to wiggle the pads out otherwise...
 

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Discussion Starter #18
Just a bit of an update...

Yesterday I put in a new set of HT-10s... after filing off the "dimple", I had no problem installing the new pads with the OEM shim plates... they dropped right in, without having to wear the front pads down at all.

On slightly different subject... is anyone able to change the rear pads without removing the calipers if you have both wheel studs and a two-piece rotor? Seems there's no way to wiggle the pads out otherwise...
Did you use brand new rotors? I was using brand new rotors with full thickness and it would not fit with the shim plates on. I had to run without shims for awhile before I could go back and put the shim plates back on.
 

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Did you use brand new rotors? I was using brand new rotors with full thickness and it would not fit with the shim plates on. I had to run without shims for awhile before I could go back and put the shim plates back on.
My rotors were new (~1000 miles), but they are Sector111 UltraDiscs, which may be just slightly thinner than a new set of factory discs. The pads and shims actually fit in quite easily :shrug:
 

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I don't care about noise, but I do care about brake fade. I assume that backing plates mitigate heat transfer from caliper/piston/rotor/pads to fluid thus cooler brakes. Not really a concern if no track days are done. But if brake fade is a concern I would keep them. I am considering these titanium plates from Hard Brakes Ti supposedly less heat transfer.
 
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