Ceramic coated aluminum bicycle rims have been around for decades, offering higher friction and durability for improved braking performance. Then disc brakes took over, offering vastly superior performance. But what if you combined the two? That’s one of the trends we saw at Taipei Cycle Show, and here are two brands with a variety of clever disc brake upgrades…

hcm aluminum disc brake rotor with ceramic coating for better braking performance

Above is the ceramic coated aluminum disc brake rotor from HSC (Huang Chieh Metal), which uses a bit of venting on the braking surface and an 8-arm structure to maximize stiffness. They use a MAO (Mico Arc Oxidation process to bond the ceramic material to the aluminum, which they developed to be able to offer these at a reasonable cost.

But why do this? Aluminum is not only lighter than the typical steel rotor, it also dissipates heat better. But, it makes a lousy braking surface. Adding the ceramic coating gives it much more friction, increases its durability, and according to their testing reduces the amount of force you need to apply at the lever by about half to accomplish the same stopping distance in dry conditions. Wet weather performance is also supposedly better.

HCM’s ceramic-alloy rotors come in at a claimed weight of 95g. We like the potential of this proven rim brake technology coming to rotors that are 2/3 or less the weight of a traditional steel rotor.

HCM multi-material disc brake rotor for road and mountain bikes with stainless steel braking surface over alloy center

HCM also makes multi-material rotors, sandwiching an aluminum core between stainless steel braking surfaces. This new version exposes more of the alloy inside the center, helping to cool it even faster. It’s similar to Shimano’s ICE rotor tech, but without the giant fins.

Brakco Ceramic Rotors & Carbon Pads

brakco aluminum disc brake rotor with ceramic coating for better braking performance

Brakco was another brand showing off ceramic alloy rotors, but with a few tweaks. Their rotors have a nice rounded edge that should keep the UCI happy, and a slotted design to shed crud. They’re also offering it with either a full 7075 alloy carrier or a combo carbon/alloy carrier. Claimed weights are as low as 49g (140mm) and 72g (160mm) for the alloy carrier, and drop even more for the carbon/alloy version…45g (140mm) and 68g (160mm)!

Both Brakco and HCM rotors require special brake pads to work with these MAO rotors.

Brakco carbon fiber backed disc brake pad for road and mountain bikes

Brakco also had these carbon fiber backed brake pads for the usual Shimano and SRAM calipers, with various pad materials on offer. The benefit? Much less heat transmission from pad to fluid. And bragging rights. Because carbon. The trick with these? They’re mostly an OEM manufacturer, so you’ll have to hope another brand picks these up. Or start importing them yourself and slap your own label on them.

25 COMMENTS

  1. “Ceramic coated aluminum bicycle rims have been around for decades, offering higher friction and durability for improved braking performance.” I have to disagree about the durability bit. I got a Mavic 217 Ceramic back around the turn of the millenium. The braking power with the harder ceramic pads was great for the time, but after some serious use, the braking surface became very smooth, almost like glass, in fact. And that was with plastic rim brake pads. With resin or metallic disc pads operating at high force levels, I wonder how long the ceramic coating on these discs will last. If their longevity is poor, they will need to be considered a rather high end wear item, or perhaps a race day upgrade.

    • I have a pair of Mavic Open Pro with cermaic coating and they are great. You do have to run special pads but after over 10 years of use in horrid conditions, they still look pretty good and brake well.

      • I wonder what is behind our very diferent experiences. My 217 Ceramic became basically unusable. By that point, disc brakes had become more popular, though, so it was a moot point.

        • The 217’s predated the Open Pro’s I believe so probably they switched the type of ceramic or at the very least their process for applying it. Although the open pros are road vs mtb, where even under the worse conditions on the road, its no constant on off of a muddy single track. I did use mine for cross a few times but the majority of the miles (I would have to guess nearly 15,000 or so) were on the road.

    • I also had ceramic 217’s as well as some Bontrager ceramic rims. The latter were better at braking, but neither had issues nor showed any significant signs of wear or change in surface. The only damage I saw was a chip section from a rock scrape.

  2. Hmm, not buying it. If this was usable Hope would have tested something similar. Ceramic discs on cars are a whole different story .

    • On cars they are a different story. I have Ceramic’s on my “Fun Car”. Pulling out of the neighborhood and city driving is an exercise in fear as until the breaks are -to temperature- they are not very confidence inspiring.

      • I would also be curious if they need heat in them. Carbon/ceramic brakes can be terrifying when on cars/motorcycles until they’re warmed up.

  3. What is it about bicyclists that so fascinates us about saving weight on brake rotors? Why?
    Thermal mass is all that keeps you from a close encounter with that tree/truck you are rapidly approaching. Yes, aluminum dissipates heat better, but 50g 3 inches from your axle is of no noticeable performance advantage.
    Cast iron would make much more sense.

    • Why cast iron?
      Cast iron has only 0.46 J/(g-°C) while aluminum has 0.921096 J/(g-°C).
      Which means you require twice the amount of energy to heat up 1 gram of aluminum compare to cast iron. Change most weight from iron to aluminum, even without the heat dissipation benefit, will still make your rotor heat twice slower.

      • Don’t forge the grams, that important mass component. While Aluminum’s specific heat is more attractive–twice as much–cast iron has a higher density (by a factor of almost 3) and thus more thermal mass. For the same heat flow, that cast iron disc will heat more slowly than an aluminum disc of the same size.

  4. Aluminum a “lousy” braking surface? That’s way off base. Aluminum has one of the highest coefficients of friction of all materials. Twice that of steel. Cast iron is almost on par with aluminum, but that’s a hard sell – putting cast iron rotors on a carbon fiber bike. Aluminum’s CF along with weight and heat dissipation, are why aluminum rim brakes work so well. Haw many of you had a Schwinn Varsity with steel rims? In the wet? Aluminum is just not as hard as steel – so with the higher forces needed on discs – wears faster. If it weren’t for the low melting temperature of aluminum – it would be the standard for cars. And attempts at high performance aluminum brake rotors in cars have been attempted many times. Bikes just aren’t going to light up rotors like the blaze on LMP1 cars at night in Le Mans.

    • The only reason cast iron is not being used on bicycles is aesthetic (it rusts) & stainless steel doesn’t. They have been used on motorcycles to great advantage.
      Here’s a fact I didn’t know….cast iron is LIGHTER than stainless steel (SG 7.03 vs. 7.7)

  5. Hope they aren’t like the other ceramic coated rotors = hard fail.
    One issue is the differential properties as between the alu carrier and the ceramic coating.
    Heat of braking expands the aluminum, but not the ceramic. Hello tree.

    The bike application is alot trickier than motos or cars.

  6. at this point normal disks are working well enough to say that any of this fancy “breakthroughs” are just sales tools to get to riders pockets.
    but its the risers choice if and on what to spend there money
    Ceramic coated rims ware good solution as the uncoated rims did not last and couldn’t provide good breaking in wet conditions..BUT… in general we see history brought the rim brakes to the bin as discs are so much beret.

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