Holding the frame, fork and wheels together, axles play a crucial role for any bicycle. Two novel axle standards address different issues while targeting both the performance and utility market segments.
Axles can be found on any wheeled vehicle, holding the wheel in place so it can spin. They represent a key structural element, adding stiffness to a system construction, with a width and diameter that can vary depending on intended use and materials used in manufacturing. In cycling, quick-release axles were in high demand for years until the rise of disc brakes shifted the favor to thru-axles, which make for an easier and more precise alignment of the caliper and rotor. For performance-oriented applications, the time needed to remove and reinstall a wheel is critical, but for utility bicycles the ease and safety of operation gets top priority. These differing priorities are reflected in two novel axle standards that have recently been introduced to the market.
With SWS (or “Switch Wheel System”), Italian supplier Fasten Bike presents a solution adaptable to all kinds of bicycles, aiming first at road and gravel bikes. The main advantage of SWS is that both the disc brake rotor and the cassette separate from the wheel when the latter is removed. Thus, there is no dangling chain and no risk that the brake caliper self-adjusts and closes up when the wheel is taken out. SWS speeds up wheel changes significantly and eliminates some of the most common headaches. To achieve this, Fasten Bike relies on three key elements: the disc support mounted on the left chainstay, the cassette holder on the right chainstay and the wheel hub that is built around a thru-axle with a diameter of 14 mm. The latter is loosened and tightened using an Allen key, and the hub sports a triangular interface that slots into fittings that remain on the frame and fork.
Another unique feature of SWS is that front and rear wheels are fully interchangeable. In races this aids the work of team mechanics and neutral service providers. As spare wheels do not include a disc or cassette, the wheels also become more affordable. The fact that the rotor and the cassette remain on the frame also comes in handy when transporting a bicycle in a bag or case. According to Fasten Bike, SWS is compatible with both Shimano and SRAM components and various rotor diameters. Frames and forks need to be designed around the system, however, with bearings to be integrated in the dropouts. Fasten Bike says it has reached the final stages of development, with first applications expected in a controlled, performance-oriented environment.
The novel TA5 system is an axle standard mainly aimed at improving safety and ease of operation while reducing compatibility-related issues on entry- to mid-level volume bikes. It was officially introduced earlier this year following a series of industry workshops, but several major brands involved in its early development had already commissioned frames with TA5-specific dropouts ahead of the public launch. The central feature of this design is its closed-type dropouts, which significantly add to safety. Since the wheel is kept in place securely, it can’t fall out even when the axle has not been tightened properly. As entry-level bicycles are often used by less experienced cyclists, the risk of incorrect operation is considerably higher.
The TA5 system relies on a steel thru-axle with a diameter of 5 mm, a robust design that proved its worth for many years when quick-release axles were still the norm. This axle is tightened to a set torque of 6 Nm and combined with a derailleur hanger and a nut to form the TA5 system. It also features a smart compatibility concept: by using adapters, TA5 allows entry-level QR-type hubs to be used in UDH-compatible thru-axle frames. This reduces the number of SKUs and simplifies logistics for bicycle manufacturers and assemblers. The developers behind TA5 also managed to reduce the number of derailleur hangers to just three variants: an inboard version, an outboard version and one compatible with UDH dropouts. Previously, entry- to mid-level bikes featured a wide variety of hangers, making service and repairs more complex.
Bicycle manufacturers who want to use the TA5 system must sign up for a free license agreement. This provides access to detailed specifications and drawings outlining the requirements for integrating the system into frame and dropout designs. Industry demonstrations and technical briefings are planned as part of ongoing outreach to brands and OEM partners.
Topics in this article
More news and updates from the Show Daily team
- Giant founder King Liu passes away
- Overview: Bicycle Drivetrains and Shifting Solutions
- Shimano State of the Nation Report: Europe’s Cycling Future Faces Hidden Barriers
- Overview Bicycle Lights: Bright Ideas Bring New Safety and Power Features
- Shimano: Financial Report Shows Bicycle Division Returning to Growth