Disc Brake FAQBoyd Johnson
All thing disc brake!
Yes… All things! There is a lot of information here, but organized into different sections.
If you have a question about anything with disc brakes it’s probably answered below.
The disc brake hubs that we build on are centerlock. There are two methods for attaching the rotor to the hub, traditional six bolt and the newer centerlock standard. Six bolt relies on tightening six individual T25 torx bolts to secure the rotor to the hub shell. Changing a rotor require removing all six of these bolts and then securing all six bolts again. It can be a time-consuming process.
With the centerlock standard the rotor fits over top of a spline and then secured via a lock ring (similar to how a cassette mounts on a freehub body). To change a rotor, you simply loosen the lock ring, slide the rotor off, and then tighten the lock ring for the new rotor.
The important thing with this is that whether your hub has six bolt or centerlock rotors, you can run them on your disc brake equipped bike. The spacing of where the brake mounts sit is universal, so if you have one wheel with a six-bolt rotor and one wheel with a centerlock rotor they are interchangeable. Note that you will need to know what size rotor your bike is running to ensure you have that size rotor on your wheels. Example, if your disc brake calipers are set for 160mm, then you need to run 160mm rotors on your wheels.
If you have six bolt rotors that you currently using and would like to use them with your centerlock splined wheels you can do that with a centerlock to six bolt adapters. This adapter will fit over the centerlock splines and has tabs to mount the six-bolt rotor. You can use your existing six bolt rotors.
If you have centerlock rotors already, you can only use them on centerlock splined wheels. Due to space requirements and needs to conform to spacing standards there is no way to run a centerlock rotor on a six-bolt disc brake hub.
Attaching the centerlock rotors
With the centerlock rotors they simply secure to the hub by tightening a lock ring (part SM-RT96). With most centerlock rotors the lock ring will be included with the rotor. It’s often referred to as the internal lockring as the splines to tighten the lockring are on the inside and you use a standard Shimano cassette tool to tighten the lock ring. The exception to this is if you order a Sram centerlock rotor. These do not come with the lockrings so you would have to find the lockrings separately.
The traditional internal lock ring that comes with the rotors will work for the axles that have an outside diameter of 19mm. This includes all rear axles (quick release, 135mm thru axle, 142mm thru axle, and 148mm boost thru axle). For the front hub, this internal lock ring can be used for quick release and 12mm thru axles. Both of those use a 19mm outside diameter on the axle.
For 15mm axles (both 15mmX100mm and the 15mmX110mm for boost hubs) the outside diameter of the axle is 21mm. With this larger outside diameter, there is not room for the cassette
tool to fit inside the lock ring and clear the axle diameter. With this you need an external lock ring (part SM-HB20). The locking part of this is on the outside of the lock ring. You need a specific tool to tighten this lock ring (it’s the same tool used to tighten the external cups on a threaded Shimano bottom bracket).
The Quest disc brake hubs feature easy to install swappable end caps to accommodate the different axle sizes that your bike may have. Each end cap is conveniently laser etched with the spec of the axle size and where on the hub the end cap belongs (rotor side or non-rotor side). To convert from one axle standard to a different one, you simply need to slide the end cap off the axle and install the new end cap on the axle. This can all be performed by hand. There are no tools required!
The Quest disc brake hubs can also very easily swap between Shimano and Sram freehub body, Sram XD driver, and a Campy freehub body. The Shimano and Sram freehub body, and the Campy freehub body uses a traditional multi-piece cassette where each cog is placed on the freehub body and a lockring is tightened to hold the cassette in place. Shimano and Sram cassettes fit on the same freehub body and are interchangeable. If you have a Campy cassette then you need a Campy freehub body.
The Sram XD driver uses a different type of cassette. This is a one-piece type of cassette that threads on like an older style threaded freehub. If you are running a Sram XD style cassette then you must use the XD driver. That cassette will not fit on a Shimano or Sram style freehub body.
Swapping the freehub body options between Shimano/Sram, Sram XD Driver, and Campy is super easy, requires no tools, and requires no redishing of the wheel afterwards.
Boost Spacing Hubs
The new standard for mountain bikes uses a wider “boost” spacing for the front and rear hubs. The axle standard for boost is 110mm X 15mm thru axle for the front and 148mm X 12mm thru axle for the rear. The hubs will come with the correct end caps installed that is the ONLY end cap that will work with the boost spacing hubs. You can still swap the freehub body between Shimano and Sram freehub body, and Sram XD driver. There are no Campy groups that are designed for bikes that would have boost spacing.
Thru Axles and Skewers
If your bike uses thru axles, the axles that thread into your frame and fork will be specific to your frame and fork. There are a few different width, threading, and size options to where we could not supply the axle without knowing exactly which bike you had. With the thru axle style axle, the axle always stays with the bike, whereas the traditional skewer style bikes, the skewers were a universal size and most people would keep a set of skewers with each set of wheels.
- If your bike is thru axle and you order the wheels with the thru axle end caps, a skewer WILL NOT be provided with the wheels as it’s not needed.
- If your bike uses a quick release skewer to secure the wheels and you order the wheels with the quick release end caps we WILL include the quick release skewers with the wheels.
- If you are ordering just the quick release end caps separately, the skewers WILL NOT come with the caps. You will have to order the quick release skewers separately here:
Swapping disc brake hubs between multiple bikes
If the two bikes you are swapping the wheels between have the same axle size and rotor size, it’s a simple removal of the wheel and installing it on the other bike. If both bikes have thru axle, you WILL NOT move the axle with the wheels. The axle will stay with the frame and fork, not the wheels.
If the bikes have different sized rotors or different axle standards then the hubs will need to swap rotors and/or end caps to fit into the new bike. Fortunately, with the Quest hubs, this is super easy to do with minimal mechanical knowledge and in almost no time required.