If you have been reading about new technologies being integrated into mountain bikes in recent months, you have likely heard about the Syntace X-12 or another 142mm axle system in some form or another. There seems to be a cloud of mystery surrounding this new product in what it is, how it works and why it is better than the alternatives.
The hubs pictured above illustrate the two most common styles of hubs on the market today. The far left is a traditional 135mm width with a 9mm axle. This is the style of hub that a standard quick release wheel uses and is used on Cross Country and some All mountain bikes. The middle option is still a 135mm width but uses a 12mm axle. This increased diameter allows for the use of a stiffer, stronger and more secure axle. This style of hub is used in All Mountain and some Freeride bikes. Once we arrive at the far right image, this is the new 142mm x 12mm hub. This hub is 7mm wider than the other two hubs while sharing the 12mm axle with the middle option.
This image is comparing the 135mm to the 142mm axle. The first thing you will notice is that the latter is wider by 3.5mm on each side. The freehub body and hub shells however will line up identically between the two options. In some cases, the only different between these two hub sizes is a set of end caps. As a result, depending out which hub you are using, it may just be a matter of purchasing an adapter kit to make your existing wheels work in a 142mm dropout.
This 3.5mm that has been added to each side of the axle does not actually affect the spacing of the cassette or brake rotor in the frame. Instead, hub caps are inset into the frame. This inset acts as a guide for installing the rear wheel while increasing the contact patch of the hub to the frame. While a traditional clamping style pinches the axle between the dropouts, this new system allows for a much stronger, stiffer and lighter clamping mechanism. It should also be mentioned that not all 142mm systems are created equal. While 142mm is stiffer than a standard 135mm axle, many of the real benefits come out of the Syntace X-12 conical clamping mechanism. This gets fairly technical so for full details on how Syntace improves axial and radial clamping, head over to syntace.com
The second aspect of the Sytace system that offers great improvement over other styles is a the utilization of a new type of derailleur hanger. In this system the frame's rear axle pinch-bolt serves a second purpose as the derailleur hanger fixing bolt.
The derailleur hanger fixing bolt mounts downward through the frame and into the derailleur hanger. In this design, an impact which would break a traditional hanger, will instead sheer the bolt leaving the hanger intact. This is accomplished by designing a breaking point in the bolt (between the threaded sections) which breaks at a calculated force which is less than that of your expensive derailleur.
To make a repair in such a circumstance one must simply remove the broken bolt using a 3mm allen key and replace the bolt with the spare that comes on every Syntace equipped Norco mountain bike. It is important to note that although this is the frame's axle pinch bolt as well - upon breaking, the integrity of the rear wheel will not be affected in any way. The rear wheel will remain secure.
The result of Syntace is a stiffer, stronger, lighter and more reliable rear wheel and drivetrain. Utilizing the Syntace X-12 system offers a number of benefits with nearly no downfall. The fact that many traditional 135x12 hubs can be converted to 142mm means that expenditure is minimal but all the benefits of the system can be realized. When you are out shopping for your next bike, keep Syntace in mind; it is here to stay.