Following Shimano's recall program for 760,000 Dura-Ace and Ultegra bonded 11-Speed road cranksets in North America, a class action lawsuit has been filed in the USA against Shimano, the world's biggest manufacturer of cycling components, for providing "inadequate cranksets" which have put cyclists across the country at risk of injuries. The bike brands Specialized and Trek are also included in the class action, accused of describing its bikes as "perfect" and "the world's best" which was not accurate due to the "defective cranksets", alleges the lawsuit.
The 72-page lawsuit claims that the defective cranksets can break without warning, often when a cyclist is riding at high speed, and could cause a crash that can easily injure a cyclist or worse, prove fatal.
The case also alleges that Shimano, Specialized and Trek were aware "for years" that the bonded components of Shimano Hollowtech II cranksets could break, yet waited until 21 September 2023 to announce a voluntary recall of the cranksets, produced between 2012 and 2019, citing a "possible bonding separation issue" in North America.
According to the lawsuit, Shimano has admitted that it was aware of at least 4,519 incidents of the bonded cranks breaking, some of which reportedly caused "significant personal injuries."
The Hollowtech II cranks includes two generations of the popular Ultegra and Dura-Ace groupsets, usually found in the higher and more expensive end of the cycling spectrum. There are estimated to be over 2.8 million bikes worldwide fitted with these cranks.
While in North America, Shimano has invoked the recall for its possibly defective cranks, in Europe, Shimano has instead issued an "inspection and replacement program" rather than a full recall.
In the UK, and since our most recent investigation and news coverage on this issue was published, the Office for Product Safety and Standards (OPSS) has published a product safety report that concluded the affected Shimano cranksets "do not meet the requirements of the General Product Safety Regulations 2005."
The US class action argues that the recall is ineffective as it allows only for the replacement of Shimano cranksets that have shown "signs of bonding separation or delamination" during an inspection, leaving riders whose cranksets have not begun to fail with no solution, and potentially at risk of a crash if their crankset later breaks during use.
The case accuses Shimano of "working hard to limit the cost of fixing the issue at the expense of consumers". According to the filing, cyclists who own bikes with the recalled cranksets have been "injured financially" as they purchased bikes that "are of a lesser standard, grade, and quality than represented" and nowhere near as safe as what should be the norm.
The lawsuit reads: "Plaintiffs and the other Class members were deprived of having a safe, defect-free crankset installed on their bicycles, and Defendants unjustly benefited from the sale of these products and from the unconscionable limitations on the recall remedy now offered."
The case also argues that cyclists will be deprived of their bikes for unknown periods of time, while trying to schedule an inspection alongside hundreds of thousands of other impacted cyclists.
Further, it says that Shimano has left the inspections of its "sophisticated" cranksets to local bike mechanics who "should not be put in the position of making complicated engineering judgements related to a critical safety issue".
road.cc has been hearing stories of cyclists whose Shimano Hollowtech cranksets were snapping underneath them for many years now, and had previously sent out a request for those affected to email us with pictures and stories about their crank failures.
In addition, road.cc sent some of the broken cranksets to Dr Mark Bingley, the Principal Lecturer and Programme Leader for Mechanical Engineering at the University of Greenwich, for further investigation and to better understand the issue.
Early findings indicated that a critical initial stage in the failure of the cranksets involves the partial separation of the inner and outer U-shaped channels, which together form the rectangular tube section of the crank arm. Despite wear and corrosion being cited as possible causes of the failure, no evidence of significant corrosion was found in the two failed cranksets that were inspected.
When road.cc asked Shimano why there was a difference between the recall in North America and inspection program elsewhere, the Japanese company said: "Shimano has been working closely with both the American Safety Authorities and their counterparts in Europe (specifically in the Netherlands), however we are unable able to provide specifics on the processes.
"This is due to the regional differences between safety authorities and their own risk assessment processes of the affected products. We were required to adhere to their respective requirements."
Shimano also said this when asked why the cranks were breaking: "Cranksets can and do break for a variety of reasons. The affected bonded cranksets have been reported to separate and break on rare occasions, thus posing a crash hazard to consumers.
"While it is difficult to draw firm conclusions from a small sample, Shimano has made numerous changes, improvements, and enhancements in response to the market information we are receiving. This is standard practice at Shimano."
However, in 2021, Shimano told us there isn't a design problem with its Hollowtech cranks despite reports of a pattern of failures, and despite the photos and tales of many misfortunes rolling ever so frequently in our inbox.
As of now, Shimano has pointed out that not all 11-speed Hollowtech II road cranksets are part of the recall and that only those produced during the specified period need to be inspected. "We expect only a very small percentage of these cranksets will need to be replaced," Shimano said.
The recall allegedly provides for free inspections at participating retailers, and if a crankset shows "signs of bonding separation or delamination during the inspection," Shimano will provide a free replacement.
The company also said that "the replaced crankset will be a special version, which may feature a different cosmetic appearance while maintaining the same level of performance."
Adwitiya joined road.cc in 2023 as a news writer after graduating with a masters in journalism from Cardiff University. His dissertation focused on active travel, which soon threw him into the deep end of covering everything related to the two-wheeled tool, and now cycling is as big a part of his life as guitars and football. He has previously covered local and national politics for Voice Wales, and also likes to writes about science, tech and the environment, if he can find the time. Living right next to the Taff trail in the Welsh capital, you can find him trying to tackle the brutal climbs in the valleys.