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Item # SHI0553
This model is no longer in stock.
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Shimano Enduro Zero 7900 Ceramic Hybrid Bottom Bracket $0.00
This Enduro Zero Ceramic Hybrid Aftermarket 7900 Bottom Bracket uses the latest hybrid ceramic bearing technology from Enduro Bearings to seriously minimize the friction inside your bottom bracket.
Unlike aerodynamic resistance which takes on serious consequence mainly at high speeds, mechanical resistance is present even at slow speeds. The drag of inferior bearings in your bottom bracket and hubs can cause a measurable increase in effort required to propel the bike. Ceramic hub bearings, for example, have been shown to provide reductions in drag on an 8% climb equivalent to dropping 340g from the weight of your bike. You don't need a degree in engineering to understand the impact this has on your performance. The reasons behind the performance upgrade are the hardness and roundness of the ceramic bearings (not to mention the cost-is-no-object lubrication bathing them).
Our Dura-Ace bottom brackets are, of course, made specifically for use with Dura-Ace cranksets (and they're also compatible with Shimano's Ultegra and 105 10-speed cranksets). By keeping your drivetrain full Dura-Ace, you're assured of top-notch performance.
We use a precision Phil Wood bearing press to remove the original Dura-Ace bearings and to install the Zero Ceramic bearings. It's a simple retrofit, and you'll get the Shimano bearings back with your package.
The Enduro Zero bearings use grade 3 Silicon Nitride ceramic balls. Remember, lower grade numbers equal higher quality ball bearings. Grades range from 2000 to 3, these being right there at the top of the heap. What it really means is that the Zero ball bearings are more consistent in size from one bearing to another, smoother, harder, and more spherical than bearings of lesser grade. These top-notch balls would be superfluous without a race of equal precision. Enduro relies on hardened chrome steel races to do the job. You might wonder why they didn't use stainless steel for their top-shelf bearings. The reason is that stainless is a good bit softer than chrome steel and is susceptible to microwelding and deterioration under heavy loads.
Enduro gives the Zero bearings a corrosion resistant Magnetite finish (essentially an iron oxide, but far removed from rust). The Magnetite coating is limited to the surfaces other than the bearing track. It offers complete protection from the elements and has a smoky grey, polished hue. The Zeros also get a new double lip seal to protect the bearing races from contamination. The bearings come packed with ceramic-specific Kyudo Yushi PS2 grease. All these details add up to create the fastest rolling ceramic hybrid bearings on the market.
The Enduro Zero Ceramic Hybrid Aftermarket 7900 Bottom Bracket is available for either English (68mm) or Italian (70mm) threading. Competitive Cyclist will provide a 3-year warranty on our retro-fit ceramic Dura-Ace bottom brackets -- the same duration as the standard Dura-Ace warranty.