# Aluminum Brake Rotors



## piotrsko (Dec 9, 2007)

depending on your brake bias adjustment, and the alum alloy, they might work. Expect a very short life ( <10K Miles)


----------



## JRP3 (Mar 7, 2008)

Certainly wouldn't be worth it if that was the lifespan. I'd think they would do better than that with the regen doing most of the work, but maybe not.


----------



## mizlplix (May 1, 2011)

With aluminum rotors, a good deal of the wear is just dust on the rotor grinding under the pads when driving. They are hard anodized and when it gets through this barrier the wear accelerates.

With regen, I could get by with just a single, thin cast iron or stainless steel solid rotor. Like on go karts or my Wilwood Dyna Lite 1's.

Aluminum calipers and mounts are good though.

Miz


----------



## RIPPERTON (Jan 26, 2010)

My 2004 CBR1000RR race bike has probably the only example in the world of a tungsten carbide coated aluminium brake rotor and yes it works very well and handles the heat too.
I could only get the rear disc to work but with about $200 worth of HVOF tungsten carbide mechanically bonded onto the 7075T6 cnced rotor weighing about 370gr.
The aluminium expands but the tungsten doesnt, it just mudcracks but doesnt flake off.
I could never get the front discs to work without becoming unparallel and bumpy.


----------



## JRP3 (Mar 7, 2008)

> With aluminum rotors, a good deal of the wear is just dust on the rotor grinding under the pads when driving. They are hard anodized and when it gets through this barrier the wear accelerates.


That doesn't sound good. Something I've always wondered about is a spring loaded, (or something), brake caliper that more positively retracts the pads from the rotors, reducing rolling resistance and wear. I did find this article about a new composite aluminum/ceramic brake rotor, but it seems they aren't ready yet, other than for motorcycles. Once again I'm ahead of the times


----------



## mizlplix (May 1, 2011)

There is a quad-ring on the caliper piston which is responsible for piston retraction. They "roll" forwards when pressure is applied and that tension is what pulls the piston back when the pressure is released. (in theory) The travel limitation is the material's ability to twist back to a normal posture. 

It is the outer pad that drags on the rotor......because the caliper is hard to drag back on the slide rails (pins). Make sure your pins are lubed and free.


There are better (but more costly) designs, like a simple retraction spring pulling the piston back. It is used on many smaller calipers and is identified by a screw and nut on the caliper housing, opposite the piston bore.

That is why F1 cars went to carbon and even carbon/kevlar rotors. They just have to throw them away often.

For a road car, stick to thin cast iron, steel or stainless steel for rotors, with piston retraction springs.

*You can make your own EV type brake system* by band saw cutting a big ventilated rotor in half and truing the remaining half on a brake lathe, then making aluminum spacers to place behind the pads to take up the space lost. 

OR cut down the rotor as mentioned above, get a caliper from something smaller and make yourself an adapter mount. You only need to make sure the rotor thickness is similar to what the new caliper needs.

I have done both. They work fine.

Miz


----------



## JRP3 (Mar 7, 2008)

Not aluminum but it solves the rust issue:
http://media.gm.com/media/us/en/gm/news.detail.html/content/Pages/news/us/en/2011/Nov/1130_fnc.html


----------



## Karter2 (Nov 17, 2011)

JRP3 said:


> I've wondered about using aluminum brake rotors for cars that have regen. Since the brakes are used much less they don't need the same durability of a steel rotor, and the aluminum would be much lighter and never rust. I was thinking of trying some in the rear of my Fiero. I see Wilwood has some but I doubt they would fit my car, and they do say not for road use. http://www.summitracing.com/search/product-line/wilwood-aluminum-brake-rotors


 Better to think of the "Ceramic" ( Metal Matrix Composite) rotors that are commercially available.
Light , wont rust,..but cost a plenty !


----------



## JRP3 (Mar 7, 2008)

Karter2 said:


> ..but cost a plenty !


Yeah, that doesn't work for me.


----------



## iti_uk (Oct 24, 2011)

How about using 2-piece rotors with a alloy bell and a non-vented friction ring? A vented friction ring might still be lighter than a one-piece steel rotor and would be a lot easier to sourse.

Light weight and without the wear problems of exotic-material friction rings.


----------



## JRP3 (Mar 7, 2008)

Helps the weight but doesn't take care of the rust issue.


----------



## iti_uk (Oct 24, 2011)

What about stainless friction rings on alloy bells?


----------



## JRP3 (Mar 7, 2008)

I like it. Unfortunately it sounds expensive, and custom.


----------



## mizlplix (May 1, 2011)

Aluminum , black anodized, almost unlimited sizes and bolt paterns.








http://www.wilwood.com/Hats/HatList.aspx











Super Alloy Drilled Rotor
Super Alloy Steel 10.50” x .16” Solid Rotors are one of Sprint racing's lightest rotor at a weight of only 1.40 pounds. Wilwood’s proprietary Super Alloy Steel greatly enhances the durability and lifespan of this rotor over comparable lightweight steel or aluminum rotors. A Drilled and scalloped design provides excellent high temperature stability, rapid heat dissipation, and consistent performance from the brake pads. The fine micro-finish surface beds quickly with new pads. It provides a cost effective, lightweight solution with quick response, long service life from the pads, and consistent braking at all temperatures.. Lowered rotating weight promotes quick acceleration, deceleration, and improved handling.

Super Alloy Steel Rotors have applications in all types of motorsports. Steel rotors provide a durable lightweight option in applications where sustained temperatures remain in the low to moderate range, and high heat spikes are only observed on an intermittent basis. This could be anything from a hard stopping drag race car at the end of a quarter mile, or a high speed stock car coming in from a qualifier at a super speedway. Steel rotors can also be found in lighter weight open wheel cars such as sprints and modifieds, and a variety of light weight, open wheel road course racers. A special alloy and proprietary manufacturing processes give these rotors high resistance to thermal distortion with excellent friction and wear characteristics against the pads. 

http://www.wilwood.com/Rotors/RotorList1.aspx?mktname=Super Alloy Drilled Rotor

I have used these before on street rods. They are really fine looking and extremely light weight.

Miz


----------



## iti_uk (Oct 24, 2011)

Miz, those look really nice! Perfect for a super-lightweight of some sort...


----------



## [email protected] (Dec 29, 2012)

LiteBrake Tech has developed the steel clad aluminum brake technology to deal with the high working temperature problem. You may visit litebrake.com for more inf.


----------



## JRP3 (Mar 7, 2008)

Interesting, I like the concept, but the steel face is still prone to rust, even more so since the positive pad retraction eliminates drag which would otherwise help clean the rust off. Unless the steel is stainless steel?


----------



## [email protected] (Dec 29, 2012)

JRP3 said:


> Interesting, I like the concept, but the steel face is still prone to rust, even more so since the positive pad retraction eliminates drag which would otherwise help clean the rust off. Unless the steel is stainless steel?


Yes, the steel face will rust if you don't drive the car for awhile. But the rust will be wiped out by the pads in a few stops. The rotor is painted with a high temperature paints a little bit over the rubbing surfaces. The initial braking will wear the overlapped paint out. We did stainless steel cladding in our early research and conducted a dyno test. The friction coefficient was too low against the common pads.


----------



## JRP3 (Mar 7, 2008)

That's the problem with EV's and regenerative braking, the brakes get used a lot less than a regular car, so even when driven they might not get cleaned off enough, hence my search for aluminum. Too bad the stainless didn't work out, though that would probably make them even more expensive.


----------



## jeff mccabe (Feb 23, 2010)

JRP3 said:


> That's the problem with EV's and regenerative braking, the brakes get used a lot less than a regular car, so even when driven they might not get cleaned off enough, hence my search for aluminum. Too bad the stainless didn't work out, though that would probably make them even more expensive.


 well I dont have regen on my Porsche, so they would work quite nicelly.
Make me some for my 928 Porsche LiteBrake !
Jeff


----------



## palmer_md (Jul 22, 2011)

How about a 914 Porsche.


----------



## [email protected] (Dec 29, 2012)

I can see the surface rust concern. Cast iron is more prone to rust than a rolled steel because of its pearlite or ferrite and graphite composite microstructure. Corrosions start at the graphite and pearlite boundaries. Although better corrosion resistance of our current steel cladding, we may need to consider the use of an even better steel without lowering friction coefficient. Thanks for the concern.

For the rotors over 12", the hat's ODs increase accordingly. However, most aluminum wheel's mounting ODs do not increase accordingly. In order to pass the heat to the wheels, the wheel's mounting ODs have to be increased so the SCA rotors can be used.


----------



## JRP3 (Mar 7, 2008)

That's where the benefits of regen comes in. Since much of the braking is done by the motor there is less use of the brakes and less heat generated, so less to dissipate. Might not need the increased transfer to the wheels. What about holes or slots to directly shed the heat?


----------



## JRP3 (Mar 7, 2008)

What about a coating on the steel parts?


> Cquence brake rotors are silver zinc plated to protect against rust and to keep them looking new.


http://www.cquence.net/cquence-street-extreme-brake-disc-rotor-rear-pontiac-fiero-1988-html.html


> All Brake Rotors are provided with our gray ZRC coating. It provides long-lasting protection against corrosion in the most hostile salt-water environments. After being applied, ZRC provides the highest level of galvanic protection. The film of ZRC is conductive. After the coating heats up during use, it bonds permanently to the metal surface. It will not allow the metal to corrode, even when the surface is scratched.


http://www.topbrakes.com/carSeriesD...024-R_17900R?gclid=CKPmz6TPwrQCFU-d4AodFGYA-A

Also, I don't know what your marketing plans are but I'd think you'd want to target more of the light sport vehicles, enthusiasts who care about weight and are willing to spend more. Not sure people driving a Town & Country would be that interested but people in the Miata, Fiero, etc. market probably would.

And for whatever reason the two times I've visited your site it's locked up my computer temporarily and caused a C runtime error, seemingly related to the videos. Might be just me.


----------



## [email protected] (Dec 29, 2012)

JRP3 said:


> That's where the benefits of regen comes in. Since much of the braking is done by the motor there is less use of the brakes and less heat generated, so less to dissipate. Might not need the increased transfer to the wheels. What about holes or slots to directly shed the heat?


Yes, a quite high percentage of kinetic energy is converted to electricity by the regen system. In the future, the rotor thickness and OD for electric and hybrid cars can be reduced. More holes and slots increase the available surface area for heat dissipation by air convection. It helps but limited. You can estimate by the surface area increase.


----------



## [email protected] (Dec 29, 2012)

JRP3 said:


> What about a coating on the steel parts?
> 
> http://www.cquence.net/cquence-street-extreme-brake-disc-rotor-rear-pontiac-fiero-1988-html.html
> 
> ...


Our ultimate target is OEM applications. Especially, we found surprising gas mileage increase during the road tests of the SCA rotors. We cannot explain the phenomenon at beginning, now believe it is primarily due to pad drag reduction. We'd like people to try the rotors on different cars and see if the phenomenon is common. The second reason is the cost of high volume production and single size of SCA rotors is not high. OEM applications may take some times. We just started the market penetration and think the performance rotor sector might be a good starting point. We welcome comments and feedback, and then go from there.

Sorry for the videos to cause your computer runtime error. The video files might be too big. We'll reduce the photo resolutions. Thanks your feedback.


----------



## JRP3 (Mar 7, 2008)

It might be because both videos start playing automatically at the same time when the page loads.


----------



## tomofreno (Mar 3, 2009)

Didn't see any listed for Suzuki Swift.
Likely not a lot of Swift owners interested in them though.
Sportscars, like JRP3 said. High end, lots of discretionary spending.


----------



## [email protected] (Dec 29, 2012)

JRP3 said:


> It might be because both videos start playing automatically at the same time when the page loads.


We have reduced the file size of rotor rotating. It seems the problem one. If not, we'll further reduce both file sizes. Thanks.


----------



## [email protected] (Dec 29, 2012)

tomofreno said:


> Didn't see any listed for Suzuki Swift.
> Likely not a lot of Swift owners interested in them though.
> Sportscars, like JRP3 said. High end, lots of discretionary spending.


 
Thanks for your advice.


----------



## JRP3 (Mar 7, 2008)

The video size change seems to have done the trick. It still hangs a bit when loading but doesn't give me the runtime error. This is when using Firefox. I just tried it in Chrome and it crashed the media player plugin, but when I click on them it goes to the youtube page and runs fine. So something is still a little funky with the embedding I think.


----------



## [email protected] (Dec 29, 2012)

JRP3 said:


> The video size change seems to have done the trick. It still hangs a bit when loading but doesn't give me the runtime error. This is when using Firefox. I just tried it in Chrome and it crashed the media player plugin, but when I click on them it goes to the youtube page and runs fine. So something is still a little funky with the embedding I think.


Very much thanks for the information. We'll try to see if we can solve the problem.


----------

