Explained: Costa’s chainring calamity and Romandie recon puncture chaos

Why chainring bolts and flint proved the main talking points of an otherwise bland time trial.

After a mechanical failure, Rui Costa ended up on his road bike for the Romandie prologue. Photo: Cor Vos

At 6.8 km in length, flat as a pancake, and with a start list lacking in time-trialling rivalries, one might have expected the Tour de Romandie prologue to go by almost unnoticed by fans, the media, and teams alike.

Not so, though, thanks to former World Champion Rui Costa’s chainring misfortune on the start line and a peculiar pre-race puncture spree which seemingly affected every team, with all seven riders on one team suffering almost simultaneous double punctures.

What happened?

Let’s break down Rui Costa’s incident first. The Portuguese rider, enjoying a renaissance so far this season, finished dead last, five minutes down on the winner and precisely three minutes behind the second-to-last rider, having suffered a mysterious mechanical on the start ramp.

View this post on Instagram

A post shared by GCN Racing (@gcn_racing)

Costa suffered a drivetrain failure as he prepared to power down the start ramp, causing him to strike his knee against the handlebars. The incident immediately caught the attention of TV commentators and spectators, with many speculating a chainring failure, most likely linked to some aftermarket carbon 1x option.

The limited footage available of the incident offers little evidence as to exactly how the failure occurred. That said, we can see Costa’s bike was equipped with a 2x chainring setup, as evidenced by the front derailleur and an inner chainring we can just about make out, which, seemingly at least, exonerates 1x.

Furthermore, flicking through the footage removes the chainring of any guilt in the incident. Not only is the chainring still entirely intact, but all four chainring bolt holes are visible with no bolts attached. Could Costa really have sheered all four chainring bolts simultaneously?

Incredibly, having spoken to Costa’s team, Intermarché – Circus – Wanty, that seems to be the case. The team was at pains to explain it is “100% behind” all its staff and partners and, as such, would not comment any further other than to say the failure resulted from chainring bolts that broke on the start line.

Escape Collective contacted the team’s crank and chainring supplier, Rotor, who were able to shine some further light on the perplexing failure.

2x bolts versus 1x bolts.

Lori Barrett, managing director at Rotor, explained a simple mix-up at the service course meant Costa’s 2x setup was assembled with shorter 1x-specific chainring bolts. The shorter bolts lacked the thread engagement necessary to withstand the high load applied by Costa’s surge to accelerate away from the start house and, as such, broke instantly.

Rotor could only solve the mystery thanks to team mechanics who had recovered the broken bolts from the start ramp. At this point, the team and Rotor instructed a complete check of all team bikes to ensure the 1x bolts hadn’t found their way into any other builds.

Costa presumably hadn’t realised he could have been minutes better off had he just not finished the prologue.

Article 2.6.006 point four of UCI regulations under chapter five on stage races states: “any rider who suffers an accident during the prologue and is unable to complete the distance shall nevertheless be permitted to race the following day and be credited with the time of the last ranked rider.”

Given the next-to-last rider was three minutes ahead of Costa, he could have saved himself the effort and achieved a better position in GC while also potentially avoiding any time-cut penalty, had the commissaires decided to enforce it, by simply not completing the course. As a wise head once said to me, “RTFM.” While the exact meaning of this abbreviation isn’t exactly family-friendly, it can be paraphrased as, “know the rules.”

Intermarché were not the only team scrambling yesterday. Reports suggest every team had suffered countless punctures during the recon earlier in the day. One team staff member painted a chaotic picture of the pits with “sealant everywhere” and “all seven riders of one team suffering double punctures.”

What caused such a puncture fest? Well, despite one team seemingly attributing the blame to glass laid down by protestors, we could find no evidence of any protest on the course yesterday.

Several other teams attributed the blame to the flint-littered surface of what appeared to be some form of shared-use path or farmer’s road the prologue course followed and 24 hours of heavy rain that preceded the time trial. Flint washed up by torrential rain could certainly wreak havoc for the very thin modern time trial tyre.

One team staff member told Escape Collective, “They were repairing the roads just last week.” Another explained, “It was definitely flint and not glass. I was picking it out of the tyres myself.”

Either way, the rain stopped, the course dried, and the organisers scrambled to bring in road sweepers between the recon and the race start. Puncture panic averted.

What did you think of this story?