BikeRadar's Tech Q&A is your chance to have any tech questions answered by our expert testing team and trusted industry sources. This time, Michael wants to understand the potential pitfalls of swapping a front wheel between two bikes.
Can I use the same disc rotor with two different brake calipers? I want to swap a front wheel between one bike with a Magura Julie brake and another with an Avid BB5 brake – both with aftermarket pads.
Michael Stepan
In short, yes – you can use the same rotor attached to your front wheel with two different calipers. However, there are potential pitfalls to be aware of, and we have a tip to improve the braking performance if you do decide to use a single rotor for both brakes.
First up, optimum braking performance will almost always be found when you use a single brand for your caliper, pad and rotor.
Brake manufacturers design their calipers and pads to mesh well with their rotors.
Besides shape, the rotor will also typically be designed to be used with the compound, be that resin or sintered, used by that brand.
The shape of the pad, and how it comes into contact with the rotor, will lead to a pattern of wear on both the pad and rotor.
If you’re swapping the rotor between different calipers, and the pads hit the rotor differently on each bike, you may find uneven wear on the rotor impacts the brake’s power and performance.
We would strongly recommend you use pads of the same material (don't mix sintered and resin across the two bikes), ideally from the same brand, across both calipers at the very least.
If you decide to keep the same rotor, you will need to bed in the pads each time you ride the bike. This process transfers the top layer of the pad onto the rotor to increase bite and consistency when braking.
Alternatively, you could buy a second rotor and swap it over when you want to use the wheel on the other bike.
Brake rotors are inexpensive, and you’d have the peace of mind of knowing you’ve got the best braking solution for each bike.
It doesn’t take more than a few minutes to swap either a six-bolt or Center Lock brake rotor.
