Price Alert. You have questions regarding a product? Share product. Print product. Perfect replacement for your stock BB. Is this review helpful? Helpful Not helpful Report. Ultra lightweight, perfect fit for my aluminium frame and is black :D.
Our top brands. Subscribe to our Newsletter Our data protection agreement data protection agreement applies. Content 2. The rigidity of the crankset ensures pedaling efficiency while its weight, a key element of the crankset, you want light, aids in cycling longer distances over which the rider needs to pedal more. Its outboard bottom bracket bearing system provides better weight distribution and more pedaling stability, allowing for more efficient power transfer.
Manufacturer item no. Description Ratings Eugen M. Dmitryi K. Show all reviews. Hide reviews. Kaj F. Andreas S. Oleg R. Nirina R. Sergey Z. Florin T. Uwe K. Marco B. Erik S. Augustin A. Markus K. Ulrich S. In addition, it uses the same bearings and cups as PF30 and BBRight and, thus, the same manufacturing tolerances and required tools. We are able to have a full carbon shell with no metal bonded into the frame, which makes for a stronger, lighter frame structure. The straighter arms also have less ankle and heel clearance than those narrower formats.
Total stiffness is not a measure of crank stiffness alone, though. Designed in conjunction with Chris King and Argonaut Cycles, T47 — announced in — is the most recent offering hoping to become the next standard.
T47 bottom brackets, aka Thread Fit 30i, use the same 46mm internal diameter as PressFit 30, but they thread into frames rather than being pressed in.
The design comes about as a solution to the well documented creaking issues associated with oversized press-fit systems. While these issues are near always the result of poor tolerances, the T47 standard promises to fix the creaking issue without sacrificing the benefits of an oversized interface.
As it stands, this new standard may just become the hot new thing among smaller manufacturers of metal bikes. The need for a heavier metal interface looked like a limiting factor for mass-produced carbon bikes, but with a manufacturer like Trek on now on board as mentioned above, its Domane features a T47 BB that could all be about to change. Threadfit Rather than press the BB86 bottom bracket directly into the frame, the ThreadFit system threads an aluminium shell into the frame first, which provides the interface for the bearings to sit in.
According to Colnago, this allows dimensions and tolerances to be controlled more accurately. Additionally, it allows the bottom bracket interface to be replaced easily if it wears over time or after multiple bottom bracket replacements. This also allows a larger 30mm spindle crank to be installed. SRAM claims that the focus on optimising the bearings resulted in a spindle diameter of Thankfully DUB has been designed with major bottom bracket standards in mind, allowing the cranks to be fitted to the most common designs with the choice of the appropriate bottom bracket.
This is achieved by placing the bearings at the same axial location along the bottom bracket axis — in the case of BB30 and PF30 bottom brackets, that results in the bearings being located outboard of the frame. Generally, your replacement cranks may have the same or smaller spindle diameter, and the same or longer spindle length than the system your bottom bracket is designed around. On the other hand, a BB30 crankset, being specifically designed for a BB30 bottom bracket is generally not adaptable to many other systems, due to the short spindle length matching the narrow shell width.
Newer BB30 cranks have started using longer spindles to make them a bit more versatile. Various other bottom bracket standards lie between these two extremes. Take these guidelines with a pinch of salt and always be sure to double check what you can fit before committing to a new crankset. And, not surprisingly, several companies are at the ready to help you make those changes.
Changing between setups typically requires some type of adapter. In general, though, the guideline is the same: try to minimise the number of parts involved. More parts added on top of each other results in greater tolerance stack-ups, plus more interfaces that could potentially creak.
How companies decide to go about that — and precisely what design features they want — is the real issue, because everyone seems to have their own ideas on how to achieve the same goals less weight, more stiffness, and lower manufacturing costs.
Threaded systems have very few limitations — they are easily cleaned and repaired at the shop level, and they do not affect the bearing fit. But the realities of relaxing tolerances can create other issues. For example, save for Shimano, Rotor, Specialized, and some FSA models that use adjustable effective crank arm-to-crank arm distance, most of these alternative systems require wave washers or compressible spacers to account for inherent shell width variability Magic Motorcycle used precision micro-shims back in the day, and some third parties offer similar systems for modern cranksets.
Things work okay if the installation is done correctly. But, if not, you could still end up with lateral play under load possibly resulting in dropped chains or bearings that are too heavily preloaded decreasing bearing lifespan.
Weather-sealing can be a problem, too.
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