- You can never really have too much braking power on a mountain bike
- For larger riders or those on e-bikes, brake fade can ruin your confidence, on those downhill sections
- Shimano and SRAM have developed new brake rotor technologies to make you stop safer
Mountain bike brakes work hard for a living, especially since the advent of e-bikes.
For years, very few mountain bikers required brakes larger than 180mm in diameter. Only extreme gravity and downhill riders needed huge brake rotors to slow them down safely.
As the e-bike has become more widely accepted, the reality of those batteries and motors have become a burden on brakes. With an e-bike being much heavier than a conventional mountain bike, those brake rotors have to deal with more rapid and prolonged heat build-up.
So what is the mountain bike industry doing to compensate?
Two of the dominant brake manufacturers are Shimano and SRAM. And they have recently shown new brake rotor technologies.
Shimano's 'Freeza' tech
The Japanese company's approach is to improve the material complexity of its brake rotors.
Shimano claims that its latest generation of brake rotors can operate better at much higher temperatures by layering aluminium between the brake rotor's steel outer structure.
The technology is called Freeza and it is now available in 180- and 203mm rotor sizes, for both the six-bolt and centre-lock mounts. According to Shimano's test data, using its Freeza structure rotor should increase brake pad life by 10%.
More material, for better braking
SRAM has taken a slightly different approach. Its new HS2 brake rotor hasn't changed metallurgy, but has become thicker.
The engineering secret to powerful mountain bike braking performance, in extreme conditions, is controlling that surge of heat generated by friction between your brake pads and steel rotors.
For SRAM, the decision has been to increase the HS2's thickness to 2mm, from a standard SRAM brake rotor's 1.85mm. That might not sound like much but it does make a difference.
In a controlled test environment, SRAM has seen the HS2 rotors deliver 7% more braking power. Ask any mountain biker who has ever overshot a corner due to brake fade, and they'll tell you that even the smallest gain – is significant.
SRAM is offering the HS2 rotor in a variety of sizes ranging from 160- to 220mm.
Are you pulling those brake levers a bit too much, without enough happening? It might be a sign of needing these new brake rotor technologies on your mountain- or e-bike.