Cycling has the power to generate many different things in people. One of these effects is becoming a sort of gear geek. We fall in love with different brands and pieces of equipment and are always looking for different ways to combine them with what we have in our ride to make them as perfect as possible.
In the case of braking, this is no exception. Some people prefer Sram, others tend to incline towards Shimano, and yet others like to mix their bike parts. Keep reading if you feel you are part of the latter group!
What are Disc Brake Rotors?
First of all, it is of great importance to know what we are talking about. Disc brake rotors are a piece of gear that, combined with other parts of a bike, help in the decreasing of speed or coming to a complete halt.
Physically speaking, they are located around the wheel axle on the side opposite to the cogs. They are in direct contact with the calipers, which, activated by the levers, press the rotor and slow the bike down.
This system is an alternative to rim brakes, which use brake pads in direct contact with the wheel. It is considered to be better in performance since rim brakes may cause overheating, damaging that part of the wheel.
Moreover, disc brakes present no counter-indications when under wet weather conditions, whereas rim brakes may not work as efficiently.
Things to Consider When Replacing Brake Rotors
If you are planning to replace your brake rotors, there are several things that you need to take into account before even looking at prices. Rotors are a vital part of the good performance of a bike, and for this, it is relevant to get the correct one for your ride.
First of all, it is very important to know what kind of assembly your rotor has. Keep in mind that six-bolt rotors can be adapted to a center-lock one, but not vice versa.
Once this is clear, you can go on with measurements. Regarding diameter, rotors vary from 140mm to 205mm (5.5 to 8 inches). There is a difference in heat dissipation—the larger, the better—but also in weight.
Last but not least, there’s thickness. In this case, information is not only important because of performance but also regarding compatibility. Check out this video on how to choose a brake rotor (credit to SickBiker):
Can You Use Sram Rotors with Shimano Brakes?
So, what about cross-compatibility? This is not too complicated to tackle. Apart from the assembly type we mentioned before, thickness is one of the most important items when trying to mix brands.
Shimano rotors tend to be 1.8mm thick, whereas Sram rotors may be 1.85 or 1.9 mm. If your caliper and pads are not compatible with your rotor, you may experience some trouble ranging from a squeaking sound when pulling the brake lever to difficulties in your braking response.
Nevertheless, you could get adapters for your brake caliper, which are designed to function correctly with different rotor thickness. There are three main standards of adapters, namely the International Standard (IS), Post Mount, and Flat Mount.
If your bike comes with post-mount brakes and 160 mm rotors, you would not need an adapter. For larger-sized rotors, you would need adapters; for instance, a 200mm rotor would require a +40mm adapter, and so on.
Sources and Useful Reading:
https://www.parktool.com/blog/repair-help/disc-brake-rotor-removal-installation
https://analogcycles.com/true-facts-about-disc-brake-adapters/