The new rim profile characterizing the Speed 55 DB is a further step forwards in the search for the best aerodynamic performance. The model therefore focuses on a demanding and "racing" audience. To improve the rolling resistance (and ultimately the speed) of the wheel/tyre system, we designed this model in the 2-WAY FIT version.
The manufacturing process of the carbon fibre rim without holes in the internal channel - a patented construction technology - also allows a stronger and sturdier construction capable of withstanding even the most extreme racing conditions. The rim with a 19 mm inner width perfectly matches recent trends of using increasingly wider tyres - a choice that further improves the aerodynamic performance of the wheel/tyre system. This data has been validated by intensive wind tunnel studies and trials where new projects are tested on a regular basis. SPEED 55 DB proved to be the best option in terms of aerodynamic penetration indexes in the Fulcrum range and is derived from the profiles developed for the tubular version used by World Tour teams.
- Tyre type: 2-Way Fit Ready (for clincher and tubeless).
- Tyre size: 28".
- Discipline: Road/Triathlon.
- ASTM category: 2.
- Rim material: Carbon.
- Front axle compatibility: HH12-100.
- Rear axle compatibility: HH12-142.
- Front wheel spokes: 21, Two-to-one (14 left - 7 right).
- Rear wheel spokes: 21, Two-to-one (7 left - 14 right).
- Spokes material: Stainless steel, double butted.
- Spokes profile: Rounded.
- Nipples: Aluminum.
- Front hub: Carbon, Aluminum oversize flange.
- Rear hub: Aluminum, oversize aluminum flange.
- Bearings: USB ceramic bearings. Adjustable Cup & Cones system.
- Plasma treated HG freewheel. Aluminum Axle.
- Weight limit: 120 kg (comprising cyclist, bike,equipment and luggage).
Tubeless technology was first used by the auto industry , then by motorcycles and now has reached the cycling industry. After its debut with mountain bikes the moment has come to "put it on the road", and that's what Fulcrum propose to do. They've developed 2-Way Fit™ technology to ensure the perfect compatibility of tubeless rims with normal clincher types and tubes. 2-Way Fit™ wheels are perfectly multipurpose for tackling every situation.
Thanks to a special impression in the valve area, the tubes are fitted with the maximum precision while keeping the tube perfectly stable inside the tyre. Housing the valve for tubeless tyres is also risk-free, with the unquestionable advantage that there are never any air infiltrations caused by non-ideal positioning when fitting. The advantages are indisputable: the tests have highlighted an unique increase in smoothness. Because there is no tube, the friction caused by rubbing against the tyre is eliminated, while the perfect adherence of the tyre to the rim prevents the dispersion of energy.
Tubeless tyres do not suffer from sudden deflation when punctured which is a great advantage in safety terms. There is also no risk of snake bites as there is no tube to rupture.
USB™ - Ceramic Ultra Smooth Bearings™
Fulcrum® has a long-standing reputation for the extremely high performance of its hubs in terms of smoothness and reliability.
In fact, all the projects are entirely developed in our R&D department and we have put obsessive care into taking care of every detail.
The hubs with USB™ ceramic bearings (Ultra Smooth Bearings) further enhance the triathlon and road bike wheels’ smoothness and reduce weight and the need for maintenance.
RDB™ Rim Dynamic Balance
The concept is simple and elegant: balance the weight of the gasket, with an item of similar weight placed on the exact opposite side.
2:1 Two to One Spoke Ratio
A system that is as simple as it is effective, the result of the ingenuity of Fulcrum® engineers and attentive observation of the results of the tests performed on the wheels on a daily basis.
These tests made it possible to understand that the forces that act on the sides of the wheels, and therefore on the spokes, are extremely different; but what’s more, the differences between the front and rear wheels are also evident and significant. The front wheel, in fact, has to remain stable even during braking of the disk on the left side, and the rear wheel, in addition to the sprocket set, has to compensate for the traction of the force on the chain side.
DRSC™ - Directionated Rim-spoke Coupling
Exclusive rim/spoke coupling system. It allows the rim, spokes, nipples and hub to align properly with the same tensioning value in all areas.
MoMag™ - Mounting Magnet
What is MoMag™? A magnet and lots of ingenuity. This was what led to the patent for the well-tested “Mounting Magnet” system, or MoMag™. How does it work? The nipples, once inserted inside the rim via the valve hole, are “guided” to the point of connection with the spoke by means of the magnet. This simple but ingenious system makes it possible to have a wheel without holes on the upper bridge, but with spokes tensioned by traditional nipples! Advantages: No holes on the rim means that the rim is uniform at every point, free from stress points or zones of weakness and, for the clincher profiles no rim tape is required, to the benefit of weight reduction. The advantages are immediately clear: greater rim lifetime, greater resistance to fatigue, the possibility to give the spokes greater tension, and greater stiffness which, in terms of performance, mean greater reactivity and acceleration. But that’s not all. The advantages also include extremely quick and simple maintenance and spoke replacement. All to the benefit of cyclists who choose Fulcrum®.
This new system raises the concept of spoking to a new level of performance for road bike and triathlon wheels ( and mtb too).
The Fulcrum® engineers have redesigned the spokes and the hub housings to create a solid and unmovable whole. The result is that the spokes:
a) will never lose their initial tension, thus keeping the wheel perfectly reactive and centered;
b) will remain in the position that have been studied in the wind tunnel tests to ensure the best aerodynamic penetration possible.
Traceability - A guarantee of quality
The keyword for Fulcrum's products is: traceable.
If you find a little label attached to any Fulcrum® product, do not remove it. It will provide you a guarantee in case of an ascertained defectiveness of a production batch, and so the component needed or wheel will be traceable.
All this because, devoted to its mission, Fulcrum® demands the absolute perfection and safety for its customers.
AFS Axle System™
The Axial Fixing System™ is the solution developed by Fulcrum® to fix the disc brake to the hub. The constraint granted by the butt area of the release mechanism, greater than in familiar standard ones, makes it possible to obtain greater structural rigidity and therefore more precise and powerful braking.
Wide Rim Tech
Fulcrum®’s R&D department, following requests from the competition circuit, has worked to create rims that are wider than before, about 4 mm or more than previously. This technical choice provides an ideal basis for 25/28mm tyres, the sizes currently popular.
This ensures stability, excellent handling and superior comfort.
Undrilled Rim Bed
No holes on the bridge connector means that the rim is uniform at every point, free from critical areas subject to stress.
The advantages are immediately clear: less weight, longer lasting rims, greater resistance to fatigue, the possibility of giving the spokes more tension and more stiffness which, in terms of performance, means improved responsiveness and acceleration.
Cup & Cone
The cup-and-cone bearing differs from the classic cartridge bearing because it works in perfect alignment with the forces involved, weight and thrust from the frame, as the bearings run in a race positioned directly opposing these forces.
Disc specific rim
Fulcrum® is one of the first wheel manufacturers on the market to offer two completely different rim profiles from disc to conventional brake. So, no adaptation, but a rim conceived based on years of design experience. Not requiring a braking track, Fulcrum®’s R&D department designed a completely new profile, aimed at saving every single gram of weight and at improving aerodynamic efficiency. Its greater width makes it a perfect fit for tyres of 25/28 mm upwards.
In line with their aim to save every possible gram of weight and to choose the most advanced technological solutions, the R&D department has developed a seamless carbon hub.
The fibre selected is woven at 90 degrees, for enhanced balance of torque when pedalling.
The Plasma treatment makes the aluminium especially hard and resistant to surface abrasion and wear. This has allowed thickness of materials to be reduced to a minimum, achieving advantages of lighter weight, while maintaining lifespan and reliability.
The Oversize Flange was developed from the need to create a system to transmit every watt to the ground without dispersion, stiffening the wheel system where necessary, without having to add spokes or superstructures that increase weight.
The oversize flange uses physics to solve the problem. It increases dishing and enables spokes to be shortened. Doubling the spokes creates a balanced system that is excellent at transmitting torque.
Monoblock hub for Disc
The rear hub of a top-quality disc brake wheel is a technical problem to be solved. Fulcrum®’s R&D department found itself facing a fundamental choice: on which side to put the oversize flange of the Two-to-one™ system? Disc or sprocket side? Without question - must stay on the sprocket side.
To combat the loss of braking power from flex and torque of the connector between the two sides of the hub, a special one-piece system has been devised with internal stiffening ribs.