Hybrid Utility

built to last

Due to the latest developments in electric motors and in pedelec concepts, it is possible to transport even larger loads while covering longer distances, often also on rougher tracks. However, this results in higher loads and charge on the wheels and their components. Hybrid Utility wheels by DT Swiss have been specifically developed and tested to cope with these increased physical strains. With an approved maximum system weight of 180 kg, the wheels provide long-lasting reliability and trust to the user.

DEVELOPMENT CHALLENGES

After considering feedback from distributors and dealers, we understood that a wheel intended for e-touring bikes had to meet specific criteria, in order to bring lasting confidence to users. If the higher loads and torques of this type of e-bike are not taken into account and the wheels are not reinforced accordingly, cracks may occur on the rim near the spoke holes or there may be possible spoke breakage in the long term. This damage can be caused by the increased weight loads on the system, but also by the rough riding surfaces and tire pressure, which have a significant impact on the durability and performance of a wheel. To resist and minimize these risks, the HU 1900 SPLINE has been developed and tested to certify a maximum system weight of 180 kg, featuring a deformation resistant rim with thicker rim walls, laced with spokes with reinforced 2.34 mm spoke heads. The reliability of the wheel comes from the quality of its assembly. All wheels are hand-laced by professionally trained wheel-builders, ensuring equal residual spoke tension in every riding situation.

reinforced rim

When the total system weight (bike plus rider) is high on less than ideal ground, the rims can deform permanently during the ride. This exposes the rim and spoke to dynamic loads which are counteracted by the rim and spoke tension. This means that the more deformation is happening on the rim, the more dynamic stress will be applied on the spoke holes and thus affect the durability of the rim and therefore, the wheel. The combination of lab tests based on real-world recorded burdens and the latest FEM analysis highlighted that the rim height has a positive and strong influence on the overall durability of the rim and thus the wheel. The higher the rim cross section, the higher the stiffness of the rim and consequently, the higher the resistance to deformation even under bigger loads. For the HU 1900 SPLINE, DT Swiss developed an extremely durable rim at a relatively low weight.

reinforced spokes

When it comes to dynamic stress, the same logic for the rim also applies to the spoke head: under high loads, the spoke heads experience a continuous dynamic load. In order to address this potential weak spot, DT Swiss has reinforced the spoke head to 2.34 mm to ensure resistance, even at a high total system weight. The output tension of the spokes also plays an important role. It is therefore essential that residual spoke tension is maintained in every riding situation, in order to keep the peak load low on the individual components of the wheel. This makes precise and knowledgeable wheel building of paramount importance. All DT Swiss wheels are assembled 100% by hand in order to pay particular attention to the tension of the spokes.

Spoke tension the hidden force

An essential factor that ensures the quality of a wheel is the spoke tension. It is this hidden force that makes a wheel durable and resistant to a high system weight. The art of wheel building is to set the spoke tension as close as possible to the given maximum, while keeping the deviation of the tensions between them as low as possible.

Spoke tension the hidden force

If the wheel is well and equally preloaded, the load is distributed to almost all spokes in the upper half of the wheel. The tension of the individual spokes increases there, while the tensions of a few spokes decreases slightly in the area of the contact patch. This means that during a wheel rotation, each spoke is maximally loaded and unloaded once. On a 29-inch wheel, this happens about 430 times on a one-kilometer-long track. If the preload is too low overall, this can lead to spokes being completely unloaded. As a result, the spokes can loosen further and are charged heavier, the wheel becomes unstable. On the other hand, if the tensions were too high at peak loads, e.g. riding in a pothole with a baggage equipped bike, the force on the spoke would be too high and the spoke would plastically deform. This over-stretching of the spokes reduces the tensions, and the wheel loses stability.

HUB SHELL & FREEHUB

Due to the battery and motor, e-touring bikes tend to weigh more than traditional touring bikes of the same category. The reinforced hub shell enables better resistance to the higher drive torques from the motors and to the heavier brake torques from the additional weight of the modern e-touring bikes; these factors improve the hub's strength and reliability. The torque of the motor and crank is transmitted via the chain to the cassette and then to the freehub body. To resist them, the Hybrid freehub bodies are made from specific hardened steel. Compared to the conventional, aluminum freehub body, the specific hardened steel offers a higher static strength. In addition, it has a higher fatigue strength. This means that even after a high number of load cycles and high peak loads occurring on accelerations, the steel freehub body offers better resistance to minor marks and wear on its surface.

RATCHET LN

The HU 1900 SPLINE wheels are equipped with the 370 hub featuring the Ratchet LN freehub system. This system allows for uniform load distribution over a large surface, where the whole front face engages, creating much smaller point loads. This provides the legendary reliability of the Ratchet System hubs. These ratchets are optimized for e-touring bikes: Made of hardened steel and equipped with 18 teeth, they offer high durability.

daniel berger
cpo

The Hybrid Revolution

«The experience gained in the meantime has now been used to develop the Hybrid Utility wheel category. Beyond their improved performance, e-touring bikes are nowadays used for a multitude of purposes, on various terrains, at a relatively high total system weight and often daily. All these factors impose considerable strains on the bike's components on a daily basis. The Hybrid Utility wheels have been built with these factors in mind: Built to last.»

NILS VERHOEVEN Manager pm wheels & components

The Hybrid Evolution

«With Hybrid Utility, we have created a wheelset for all ambitious e-touring riders that allows you to concentrate fully on your everyday tasks; whether it's on the way to work, over rough terrain or shopping for the whole family. The limiting factor in the long term must not be the wheel. Due to the significantly stiffer rim, it deforms less and the spoke tension remains at a high level even under higher loads. This has an enormous influence on the durability of the wheels and thus achieves a significantly longer service life than our competitors.»