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ENGINEERING

Because at Nine Gs we strongly believe that applied technology should go beyond marketing talk to create great products that are not only light and fast, but also functional and durable, our Aerospace Engineers apply the same systematic approach to design and manufacturing optimization that results in safe, reliable, and high performance aircraft to our cycling components.

An integrated set of technologies including Engineering methods, materials, processes, and features characterize the high quality of Nine Gs products:

Nine Gs Wheel Geometry and Configuration
The aerodynamic drag of conventional wheels is dominated by air turbulence caused by spokes and by interference of the wheels with other components, such as forks, frame, pedals, and more importantly with the rider. Contrary to the widespread perception that exotic rim sections and surfaces create substantial benefits, the fact is that their contribution is limited. The best contributions for drag reduction from the rim for a non-disk conventional spoked wheel are a section that minimizes air flow disturbance for the spokes, and its depth. A deeper, stronger rim helps by reducing both the necessary number of spokes and the spoke length. Unfortunately, reducing the number of spokes also makes a wheel more flexible laterally. Also, increasing the rim depth to reduce spoke length, enlarges the rim surface which in turn causes instability at higher speeds in cross-wind conditions, or descending. A solution which balances all of these characteristics and optimizes all design parameters is required. Nine Gs rims are offered with several depths for different applications and their sections are optimized for minimum total drag for excellent aerodynamics, and minimum lift for added stability. The rims are designed with  proprietary sections and a unique geometry that minimizes total drag by forming an early air bubble within the boundary layer. For low lateral wind angles the bubble energizes the boundary layer and promotes turbulent flow delaying its separation. More importantly than minimizing drag for the rim, the main objective of this design solution is not to disturb the airstream providing a smoother flow to the spokes. At high speed and high lateral wind angles, the bubble does the opposite accelerating boundary layer separation to break the pressure distribution (minimize lift), enhancing wheel stability in crosswind situations or descending. Nine Gs wheels are  equipped with aerodynamic (bladed) spokes, and configured with the minimum number of spokes and lacing that guarantees an extremely strong and stiff wheel (20 front -radial, 24 rear -2xCross).

Nine Gs wheels have a balanced geometry and configuration that harmonizes structural and aerodynamic design solutions for optimal performance.

Nine Gs High Performance Braking
Good braking has been one of the most difficult technical challenges for full carbon wheels. On one hand, the smooth hard and slippery epoxy surface of an untreated rim braking wall does not provide enough friction for high performance braking. This is aggravated by wet conditions, which make braking  dangerous. On the other hand, carbon-epoxy materials cannot diffuse heat very well. The increase in temperature affects not only the dimensional stability of the rim, but also the adhesive bond of the tire on tubular rims. Again, the consequences are dangerous and undesirable. Most carbon rim manufacturers have implemented solutions that treat the braking surface with extra layers of materials such as ceramics. Instead, Nine Gs came up with a very innovative solution by using a special epoxy resin and treating the rim braking wall geometry. The braking surface is not smooth, but serrated. The corrugated surface increases friction with the brake pad and at the same time increases heat dissipation. The pattern creates a braking surface that has the performance characteristics of an aluminum rim - smooth, consistent and powerful. Its appearance is similar to that of a machined aluminum rim. This surface is also very resilient to wear and able to withstand even the toughest conditions such as mud, sand, rain, and very high mileage.

Nine Gs carbon wheels exhibit the highest braking performance for both dry and wet conditions thanks to an innovative proprietary - patent pending solution, using a special material and a unique geometry for the braking wall.

Nine Gs Carbon-Aluminum Clincher Rim Design
The main design concern for the carbon-aluminum clincher rims is the structural integrity of the interface between the carbon rim body and the aluminum clincher braking wall and tire bed. For structural aluminum-carbon rims with spokes attached to the carbon body, adhesives and/or mechanical fasteners may not be strong enough to prevent the failure (detachment or disbonding) at the interface of the two materials due to the strains caused by different coefficients of thermal expansion. This situation is critical at high speed during braking because of the increase in temperature caused by friction of the brake pads on the aluminum braking walls. Nine Gs has approached this problem within the manufacturing process by mechanically joining the two materials before curing. Once the resin has finalized the crosslinking process, the two parts are integrated and permanently attached around the whole perimeter of the rim providing an extremely strong joint. To prevent the well-known degradation due to corrosion between carbon and aluminum, the surfaces of the two materials are properly isolated to avoid direct contact. The design solution for the aluminum-carbon joint is patent pending.

Nine Gs carbon-aluminum clincher rims feature a mechanical joint with extremely high structural integrity, durability and longevity.

NINE GS - PERFORMANCE CYCLING BEYOND LIMITS ™