[F87source]

Credit: F87Source



Introduction:

In this review I will be going over the Paragon Brakes Titanium Brake Pad Shims for my 2017 BMW M2 with the 4 pot front and 2 pot rear blue M sport brakes, however Paragon makes titanium shims for a lot of different BMW models so you can check their website to see if they have shims for your BMW.

I will also be going over why I think titanium brake pad shims are an absolute must for any vehicle that sees track use, and why I think Paragon overall offers the best titanium shims on the market.


If you want to purchase titanium shims for your F8X BMW here’s are some links:

Front shims: https://paragonbrakes.com/paragon-pp...ake-pad-shims/
Rear shims: https://paragonbrakes.com/paragon-pp...ake-pad-shims/



Disclaimer:

Damage/Injury Disclaimer: Any information, guidance, technical advice, coding advice, tuning advice, datalogging advice, installation instruction, calculation, experiment, safety information, or product installation demonstrated in my reviews is to be consumed and or done at your own risk. I will not be responsible for personal injuries, injuries to others or any living being, or any damage to your car, or any property damage.

Monetary disclaimer: I do not make commission, or profits or any kind of monetary gain from the sale of the Paragon Titanium Brake Pad Shims.

Sponsorship disclaimer: The way my reviews work is that I determine what product that I want to buy and actually use on my own car, and during this process the product that I end up choosing is what I believe is the best option on the market. I then reach out to the company offering the product and ask them if they would be willing to sponsor me in a review, if the answer is yes then I write a review, if the answer is no I would end up buying the product (sometimes at a later date) but I wouldn’t complete a detailed review about it (I might write something, but not to the same extent as my standard reviews). But the critical thing is that I reach out for a sponsorship and not the other way around, this means that the products I am reviewing are actually things I believe in and would use on my own car. This also means that I am not being paid to review something I do not care about. Would I do a review if a sponsor reached out to me? The answer would depend on if I believed in the product, and I would make it clear in my review if this were the case. But at the time of writing this review, such an interaction has not occurred yet.


Time of writing disclaimer: everything I am writing about in this review is described at the time of writing and may not be updated in the future, so there is a potential that things are no longer accurate in my comparisons as parts are changed and upgraded as time passes.


Bias and comparison disclaimer: Throughout this review I will attempt to be as unbiased as possible while drawing comparisons to other products.


Mistakes and Inaccuracies Disclaimer: Throughout my review I will try to be as factually accurate as possible, but there are always chances that I make mistakes and write things that are incorrect/false. If this is the case please point it out to me and if indeed it is true that I am incorrect, I will correct these mistakes and apologize for them. Afterall I am only human, so mistakes can and will inevitably happen.


Subjective Disclaimer: Please note, these reviews are also written in my own opinion, so when I am comparing different products to determine what I see as the best, there are many factors that I go through to form this opinion. Obviously there will be disagreements between people, so I will do my best to objectively determine what I deem to be the best, but at the end of the day it is still just my own opinion whether it be right or wrong. Take whatever I say in my reviews with a grain of salt.



Image Credits:

Images and videos used in this review are all property of their rightful owners as credited below each image, I am just using them for the purpose of this review but if you (the owner of the image) would like them removed please let me know via pm. Otherwise thanks to the respective image owners (I made sure to credit your online name and link where I found the photo) of the photos, without you this review would be so much more bland.



Review Disclaimer:

First and foremost I would like to thank Paragon Brakes for agreeing to sponsor me for this review. Despite this I will remain as unbiased as possible during the review. Please note, the dynamics of this relationship was that I reached out for a sponsorship review and not the other way around. This should demonstrate how I truly feel about these Titanium Brake Pad Shims - in the sense that I truly believe it is an absolute necessity for anyone who tracks their car, and that Paragon has the best offering on the market. In fact I actually have these Titanium Brake Pad Shims installed on my own m2 as of now, and I really like the added protection they will offer my brakes for future track days.




Methods of Heat Transfer to a Brake Caliper:

Let's begin this review by first going over how heat is transferred to the brake caliper itself, because this will be important later on when we discuss the function of Titanium Brake Pad Shims.



Credit: Oklahoma Climatological Survey https://okfirst.mesonet.org/train/me...tTransfer.html


The first thing to note is how heat is transferred in general, and the image above does an excellent job summarizing the 3 main ways heat is transferred. The first method is conduction, and this is when heat is transferred via physical contact between 2 objects. The second method is via convection, where heat is transferred between objects via the movement of a fluid medium - in the case of brakes the fluid would be air. The third method of heat transfer is via thermal radiation, where a hot object gives off electromagnetic radiation typically infrared radiation like in the case of brakes (as brakes don’t get hot enough to emit X-Rays, Gamma rays etc like astronomical bodies would) and that transfers heat energy to the object’s surroundings.


Now that we know the 3 basic methods for heat transfer let's examine how heat is transferred to a brake caliper. Note: this may seem trivial, but heat is generated via friction from the brake pads contacting the rotors. This friction then heats up the brake pads and the rotors, from there how does the heat get into the calipers?


Credit: S.Deshpande et al. 2017 DOI:10.17577/IJERTV6IS060119


Referring to the diagram in the image directly above we notice that heat is transferred to the brake calipers in the following ways:

1) Conduction: from the brake pads which touch the brake calipers via: the pad slides which the pads sit on, the brake caliper pistons which touch the back of the pads, and a few other indirect ways such as touching the brake pad retaining clip and pins which in turn touch the caliper. This is the main source of heat transfer to the caliper body, as the brake pads slides and piston area of the caliper forms the majority of the caliper body.

2) Convection: where the hot air from the brake rotor will flow outwards and heat up the brake caliper. Heat from the brake pads themselves can also heat the caliper by convection as well. This is less impactful compared to conduction because cool air (via ducts on modern day cars, or via clever underbody diffusers like on the OG m2) is also funneled towards the caliper and it lowers the overall temperature of the hot air.

3) Radiation: this method isn’t labeled on the diagram, but when you heat up the brake rotors until it is glowing red, they absolutely radiate tons of heat off onto the calipers. The brake pads can get hot enough to radiate heat onto the calipers as well. This is also less impactful than conduction but likely more impactful than convection, because the rotors radiate the most heat compared to the brake pads and the caliper body is mostly shielded from the rotor via the brake pads being in the way. The pads also do radiate a lot of their heat into the calipers but they more so conduct the heat due to physical contact.

4) There are some other minor details that can transfer heat into the calipers, such as the brake fluid being forced under pressure to create the braking force and that heats up the fluid and in turn heats the caliper. Or the movement of the pistons in the caliper creating friction between the seals and also generating heat. But these are very minor aspects and will not be accounted for.


So these are the ways that heat can be transferred to the brake calipers.



What are Titanium Brake Pad Shims?:

Next we will go over what Titanium Brake Pad Shims are used for.


First let’s talk about what brake pad shims in general are used for. Generally Brake Pad Shims are thin spacers used to reduce rattling, squealing and general noises from the braking system by fitting between the caliper and the pad to make up for any small tolerance differences and absorbing vibration. These shims are also not mandatory and are only there for sound reduction. These factory shims are typically made of thin metal (aluminum or carbon steel) or even rubber.


Titanium Brake Pad Shims on the other hand were made for a completely different purpose (but also function to reduce rattling and squealing because they are still a shim, just made of titanium), and their purpose was to help insulate the brake caliper from heat generated by the brake pads during braking. So these Titanium Brake Pad Shims sit between the brake caliper and the Brake Pad just like a normal shim, but due to their titanium construction do a better job of insulating the brake calipers from heat conduction and heat radiation (more on this later). This overall reduces the amount of heat transfer to the brake caliper - which is the intended goal.



Why Titanium?:

The next topic I would like to discuss is why Grade 5 titanium (6AL-4V / ASTM B348) is used for these Brake Pad Shims instead of other common metals like: 6061 aluminum, pure aluminum, 7075 aluminum, or 304 stainless steel. To make things simple it has to come down to thermal conductivity of grade 5 titanium being significantly lower than all of these other metals. It has nothing to do with titanium’s rigidity, strength, or heat tolerance because shims don’t add strength to the brake pad, and we aren’t going to be reaching temperatures that will melt the materials like aluminum (otherwise the aluminum brake caliper itself would melt) it is simply about thermal conductivity.


So let’s analyze the thermal conductivities of these metals:
1) Grade 5 titanium (6AL-4V / ASTM B348): It has a thermal conductivity from 7.1 - 7.3 W/m.K
Source: https://www.azom.com/properties.aspx?ArticleID=1547

2) 6061 Aluminium: It has a thermal conductivity of 167 W/mK
Source: https://www.azom.com/article.aspx?ArticleID=6636

3) 99.5% pure Aluminum: It has a thermal conductivity of 205 - 213 W/mK
Source: https://www.azom.com/properties.aspx?ArticleID=309

4) 7075 Aluminium: It has a thermal conductivity of 130 W/mK
Source: https://www.matweb.com/search/DataSh...bbf43f79c51b7d

5) 304 Stainless Steel: It has a thermal conductivity of 16.2 W/mK
Source: https://asm.matweb.com/search/Specif...bassnum=mq304a


So as you can see, grade 5 titanium has the lowest thermal conductivity out of all these commonly used metals, and titanium alloys in general have some of the lowest thermal conductivities among all metals. If you look at the data above, titanium is ~50% less thermally conductive than 304 stainless steel, and approximately 18 - 30 times less conductive than the commonly used types of aluminum. This is quite a significant difference in thermal conductivity, and the primary reason why titanium is used as brake pad shims.

Note: There are some metals with significantly lower thermal conductivities than titanium, but they aren’t suitable for use as shims due to them being weak/brittle, toxic, or quite expensive (selenium and tellurium are examples).



Why are Titanium Brake Pad Shims needed?:

Now moving on to perhaps the most critical question - why are Titanium Brake Pad Shims even needed if normal shims are only optional? To answer that question we need to analyze the effects of heat on the brake calipers themselves. Check out my review on the Paragon Brake Caliper Temperature Stickers for more information about why it is so important to keep tabs on your brake caliper temps: https://f87.bimmerpost.com/forums/sh....php?t=2045119

Now if you track your BMW a lot, you will notice that these brakes get hot - and this is due to the high curb weights of our cars along with the incredibly high capability of our cars allowing us to push harder and faster meaning we are reaching higher speeds and thus there is more work for the brakes to do to slow us down. So over time due to this incredibly high heat, the paint on the blue brakes will eventually shift and discolor into a garbage bag green type of color, for instance these brakes below:


Credit: K8_M235i https://www.2addicts.com/forums/show....php?t=1747800


With Titanium Brake Pad Shims installed, they will help reduce the amount of heat transferred into the brake calipers (they will insulate the brake calipers from thermal conduction of heat via brake piston to brake pad contact, and they will help insulate the brake caliper from thermal radiation from the brake pads) themselves and this should help prolong your caliper’s paint.


Now the issues don’t end there with calipers discoloring, there are much more critical issues at play. For instance if the brake calipers get too hot, the internal seals and external dust boots can begin to fail. Damaged internal seals can in turn cause the calipers to leak meaning catastrophic brake failure is imminent, or damaged external dust seals can allow debris into the caliper and also cause damage to the internal seals or they can just jam the pistons up and seize the caliper.

For example:


Credit: K8_M235i https://www.2addicts.com/forums/show....php?t=1747800



Credit: jfritz27 https://f80.bimmerpost.com/forums/sh...69&postcount=6



Credit: jfritz27 https://f80.bimmerpost.com/forums/sh...69&postcount=6


These individuals experienced their external dust boots fail due to high on brake temperatures experienced on track. Titanium Brake Pad Shims can help lower the temperatures the caliper and seals see by reducing conductive thermal transfer and also reducing radiative thermal transfer, and this will help the seals last longer.


Having shims can also lower brake fluid temperatures and thereby reduce brake fade as well, so that is another benefit.


So these are the reasons why Titanium Brake Pad Shims are a must have for anyone who tracks their car.



Paragon Brakes Titanium Brake Pad Shims:


Credit: F87Source


Credit: F87Source


Credit: F87Source


Credit: F87Source


Credit: F87Source


Credit: F87Source


Credit: F87Source


Now let’s talk about the Paragon Brakes Titanium Brake Pad Shims themselves.

Paragon uses 0.5 mm thick Grade 5 titanium (6AL-4V / ASTM B348) to make their pads, so they are using the correct material for the job. They then cut the titanium to the exact shape as the brake pad for the brake caliper so it will be a perfect fit. Paragon also doesn’t use the thickest possible sheet of titanium, and this is for good reason. Because if you go too thick on a shim your risk fitment issues and forcing the pad to push against the rotor too hard which will cause unnecessary friction, wear, and thermal build up.

Each kit will also come as sets of 4, as each caliper requires 2 shims. So the front kit has 4 shims (2 per caliper) and the rear kit has 4 shims (again 2 per caliper). But the best part is that Paragon from my research offers the most affordable shims on the market, they are easily $10 - $20 cheaper than the competition and offer an immensely high quality product. Paragon is also based in the US and has a team offering fantastic customer service, which is a major benefit as the previous options were Ebay offerings from overseas. So overall the the fact that Paragon uses the correct materials, has fantastic customer service, and has the best prices is what makes me say that these are the best shims on the market.



Installation Tips:

So moving on let's talk about installation tips, I will just go over the general basics because I will assume that you are able to remove the brake pads from your car. If not these are some very good videos demonstrating this (just don’t remove the calipers or rotors):

1) So the first tip is that you will need a good quality brake pad punch kit, the ones I used had a 1/8“ punch and a 3/32” punch, these fit the best. If you’re in Canada you can find the exact kit I used from Princess Auto (if you’re in the US and want this, I think Princess Auto ships to the US as well): https://www.princessauto.com/en/9-pc...t/PA0008548208

I also bought some small stubby hammers to help with hammering the pins: https://www.princessauto.com/en/2-pc...t/PA0008968448

2) Remove the brake pads and disconnect the wear sensor from the car, but don’t remove the sensor from the pad as that will damage the adhesive, and remove the stock brake shims - these will not go back on.

3) Clean the caliper and back of the pads from any old grease that remains, use non-chlorinated brake cleaner. I used the CRC brake cleaner also from Princess Auto: https://www.princessauto.com/en/non-...t/PA0009102997

4) Apply a small amount of brake grease between the back of the pad and the shims and then apply some grease on the brake pad ears and brake pad slides on the calipers (do not get any grease on the friction material. You can also apply a small amount of grease on the brake caliper pistons as well. I used ATE plastilube from FCP euro: https://www.fcpeuro.com/products/brake-pad-silicone.


5) Reinstall the pads and you are done!


Note: if you track your car you should use high temperature brake grease, ATE plastilube has a 100C flash point according to ATE so that will not cut it on track (when I hit the track I’ll swap over to permatex ceramic, but for the time being I am using ATE). You should use some ceramic high temp brake grease, and maybe don’t put it on the pistons (everywhere else is fine) incase the heat cooks it as you don’t want that to coat your pistons and seals.



Installed Images:

Now here are some images of the shims during and after they have been installed:


Front shims:


Credit: F87Source


Credit: F87Source



Rear shims:


Credit: F87Source


Credit: F87Source

As you can see by the images, the front and rear shims are perfectly cut the shape of the brake pads and fit perfectly without issue. They are also thin enough that they do not cause any issues with clearance and I don’t experience any squealing or rattling with them installed. You can also see them in the images above sitting in front of the brake pad when installed on the caliper. Overall I don’t have anything bad to say about these shims, they are an excellent product.



Summary:

So overall I think Titanium brake pad shims are an absolute must if you track your car, because they can help lengthen the time it takes for the caliper to discolor due to heat (or potentially outright prevent it), they can help reduce brake fade, and they can help prevent seal damage on your brake calipers. So if you want to get some Titanium Brake Pad Shims, Paragon brakes are the place to buy them as they use the correct material (grade 5 titanium), have the best prices, and have great customer service!


If you want to purchase titanium shims for your F8X BMW here’s are some links:

Front shims: https://paragonbrakes.com/paragon-pp...ake-pad-shims/
Rear shims: https://paragonbrakes.com/paragon-pp...ake-pad-shims/

[F87source]

Reserved for future posts.

[Bee Pee]

Wrong sub-forum ???

[F87source]

Originally Posted by Bee Pee

Wrong sub-forum ???

Nope, paragon sells shims for the G20 as well so this review is just a show case of the product on another BMW for anyone interested in them. So pretty much you get to see fitment on a BMW caliper and quality of the product before hand, and you don't end up buying something sight unseen.

And as far as I can tell I am the first and only person on bimmerpost to show high quality images of titanium shims, and how they fit to the pad and what they look like once installed, threads before this was just discussion without images. And I am defintely the first to review the paragon shims on here. I am also the first one to share a source for high quality shims that isn't an ebay store, and these shims are also significantly cheaper than all prior offerings shared on bimmerpost.

[Bee Pee]

Better to do a review of their G2x product on G2x sub-forum. Just saying

[F87source]

Originally Posted by Bee Pee

Better to do a review of their G2x product on G2x sub-forum. Just saying

It's essentially the same thing just a different shape.

The important thing to see is the quality of their manufacturing and who good their tolerances are. If they do a good job on the f8x pad shape then it's pretty much guaranteed to be perfect for all other applications, because it means they're able to measure a brake pad and their plasma cutters have good tolerances. It also means their titanium stock is also good quality and not horrible quality.


It also wouldn't make sense for me to just review the g2x shim alone because I'd just hold a piece of metal and can't show pad fitment or caliper fitment...

[mike@x-ph.com]

Thank you for the review