Weight: 655 grams (36-52, 172.5mm)
The outgoing 9000 Dura Ace series has been replaced by the upgraded and revised 9100 series group from Shimano. The 9100 groupset remains as 11 speed despite some hopes that it would be implemented with 12 speed. There are 4 main variations of the 9100 series including mechanical shifters and rim brakes (9100), mechanical shifters and disc brakes (9120), electronic shifting and rim brakes (9150 Di2), and electronic shifting and disc brakes (9170 Di2).
Although each of the groupsets will have unique shifters, brakes and derailleurs; one constant is the crankset. Since the 9100 crankset is independent of the type of braking or shifting, it is compatible with all 4 variations of the Dura Ace group.
The 9100 chainset uses only double rings with options ranging from 50/34 to 55-42. In between combinations are the 52/36, 53/39, and 54/42 ring combinations. The chainrings can be easily swapped and subbed because they all share the same 110 mm bolt circle diameter.
Crank lengths include a range between 165mm and 180mm. With 2.5mm increments in between, there should be a combination for everyone. The most common sizes for crank arm length are 172.5 mm and 175 mm.
This crankset is also available as a power meter. Shimano is offering for the first time a built-in power meter but at a much higher cost. This is an upgrade option and is also Shimano’s first attempt at a power meter. It should be noted that there have been some initial performance issues with this first iteration. Stay posted to see if they can resolve these issues.
As noted, the weight for a 52/36 with 172.5mm length crank arms is 655 grams. The entire crank body is anodized aluminum with the cranks arms being forged and bonded in two pieces. This makes them oversize and hollow. They are essentially a thin shell. Shimano is also sticking with its 24mm steel axle. Many manufacturers currently use oversize 30 mm aluminum axles but Shimano has had long term success using steel and for the purposes of durability it seems like a good decision. The chainring spider has four asymmetrically spaced arms which allows concentrated material and strength at the high force positions. There is plenty of reinforcement including in the outer chainring to support the most demanding power applications.
Subtle design changes allow the crankset to be compatible with disc brake frames while maintaining the same q-factor (distance between pedals) of 146mm.
How does the 9100 crankset perform? Well, Shimano is renowned for quality components and the crankset has a long history of reliability. The hollowtech II standard has been used for several previous generations and is a reliable stalwart. Other manufacturers have transitioned to carbon cranks and aluminum axles but Shimano has continued with aluminum construction and steel axles. The dura ace crank arms are a thin sandwich two-piece construction which makes them robust and lightweight while being hollow.
As always, the shifting is flawless between inner and outer rings. The chain shifts with precision and is always reliable. There is little hesitation as the chain jumps between the small and big ring. The shifters make the process smooth and effortless.
Although the style of the crank is sometimes a point of contention with people, it seems either some like it but some don’t find it aesthetically pleasing. The entire crank is anodized black unlike previous generations which feature a raw natural metal finish. The anodized black finish seems like a conservative choice by Shimano. It lacks the flash and classiness of the two-tone raw finish of past generations but provides a subtle, stealth appearance.
The 9100 crankset is best paired with a 11 speed Shimano chain. There are a variety of technologies and design features incorporated into the chain that make it work smoothly with the 9100 groupset. The chain has asymmetric links with hollow pins. The links and rollers are coated with PTFE which Shimano calls Sil-Tec. It is now possible to get a quick link for easier assembly. The uncut Dura Ace 9100 chain weighs 250 grams.
Mating the crankset to a Shimano Dura Ace bottom bracket works best. This will depend on the bottom bracket standard of your frame. If it accommodates the Shimano standard than there is both press fit and threaded models to suit that weigh in at approximately 55 grams. Frames such as the new Specialized Tarmac SL7 are now designed to use the BSA threaded bottom bracket standard. This is a change from press fit and it seems the reliability of threaded bottom brackets outweighs any small performance or weight benefits typical of press fit frames.
Overall, the Dura Ace 9100 crankset works as well as one could expect. Shimano has a long history of reliable and durable components that work flawlessly. They tend not to reach too far away from what they know works. This crankset is no exception. While conservative in style and materials, it is likely to outlast many bikes over the years. By replacing the chain on a regular maintenance schedule based on kilometers ridden, this crankset should last many years if not decades.