Christian Prudhomme’s recent claim that modern peloton speeds are so high they’re harming safety was more than one man’s opinion. The comments, made at a mid-November meeting of the bike race organizers association (AIOCC), sparked much discussion, and as sources told Escape Collective, the UCI is already investigating the issue.
Last week, we explored five potential ways the UCI could enforce a slowdown in the WorldTour peloton, following Prudhomme’s comments. But multiple WorldTour and industry sources shared with Escape that the UCI was already considering at least three of the ideas we explored –a maximum rim depth, a gearing limit, and updates to handlebar width and lever angle rules – and may soon implement new regulations specifically targeting a forced reduction in racing speeds in the name of improved safety.
The proposed measures take a combination approach intended to both make riders and bikes less aerodynamic and – at least in theory – cap top speeds by restricting the gearing riders have to push. But it’s not been plain sailing for the UCI, with industry kickback. Our sources voiced doubt that such interventions will even work.
As the UCI deliberates on new equipment regulations aimed at improving race safety and controlling speeds, it’s clear that the proposed measures could spark significant backlash. While some ideas have gained tentative support, others have faced outright skepticism from riders, teams, and industry insiders who question their effectiveness, fairness, and potential unintended consequences. Here’s what the UCI is considering.
Too deep = too aero?
Least contentious is the matter of rim depth. Industry sources present at these meetings indicate the UCI is currently exploring a 65 mm cap on rim depth in the belief that excessively deep rims are both more difficult to handle – especially in blustery conditions – and make for faster speeds in races.
The UCI has not responded to Escape‘s request for comment on potential rule changes. But a World Federation for Sporting Goods Industry (WFSGI) document submitted to the UCI and seen by Escape argues such a rule change is unnecessary and ineffective in improving race safety. The WFSGI document highlights that there are very few examples of riders racing with rims deeper than 62 mm, and points to the fact that of the 283 companies which have rims registered with the UCI, just 42 have registered rims with a depth greater than 80 mm and only eight of those have been registered in the past four years.
The WFSGI’s conclusion – largely borne out by even a cursory glance at the WorldTour peloton in any mass-start race – is that this data “proves that the ridden rim heights in road cycling seem to remain constant and there is no trend noticeable towards higher rims over the past few years.” That finding definitely rings a bell for us, having investigated where have all the deep wheels gone at last year’s Tour de France
No one disputes that deeper rims can contribute to higher speeds, and, unsurprisingly, the WFSGI accepts as much. But the organisation argues other characteristics of modern wheel-tyre systems besides rim height “significantly influence aerodynamics and riding speed.” The document points to features like “a well-matched wheel-tyre system,” plus “the shape of the rim and components like the spokes and hubs of the wheel.”
The document also contends that a lower rim height does not inherently lead to reduced steering moments in crosswind conditions or guarantee improved handling predictability, instead arguing that crosswind sensitivity depends on many technical characteristics of the entire wheel-tyre system and is additionally influenced by factors such as rider weight and experience.
The WFSGI concludes that a rim height limit is not seen as an effective measure for improving rider safety within the cycling industry and suggests any such limits are typically for aesthetic purposes.
Instead, the industry group proposes a 100 mm rim height limit for mass start competitions, which it says would maintain the current standard while preventing potential future extremes, That feels akin to no rule, given nobody rides wheels anywhere close to 100 mm in depth and certainly not in mass-start races that are the focus of the potential regulations. But the WFSGI argues this approach ensures sufficient freedom for innovation, enabling the continued development of safe and high-performance cycling equipment.
Unlike the other new rules up for consideration at the UCI, though, a limit on wheel depth wasn’t entirely dismissed by everyone we spoke to. One industry source who works with various teams but was not in attendance at the meetings told Escape that “limiting rim depth isn’t a terrible idea but no one is going silly with it yet,” while a performance consultant and coach with one WorldTour team told us that restrictions on wheels “is the one area that actually would be fairer across the field.”
It is as yet unclear which way the UCI will ultimately decide on rim depth, with one source with knowledge of the meetings indicating the WFSGI was successful in knocking back the UCI’s plans, while another was much less confident that is the case.
Too narrow = too aero?
The UCI is also investigating new minimum handlebar and lever width proposals. While it implemented a minimum 35 cm handlebar width rule two years ago, and followed that up with a maximum 10° inward lever inclination rule just 12 months ago, it is now looking to restrict cockpit setups even further with a regulation mandating a minimum inner lever width.
Both the handlebar width and lever angle rules have their loopholes, offering riders the chance to adopt narrower positions the UCI had hoped to outlaw. For example, because the UCI had limited the minimum outer width of the handlebar, designers could adopt much narrower widths at the levers and then flare the drops out to hit the 35 cm minimum required by the UCI. Subsequently, because the maximum 10° angle permitted for levers is in relation to the drops, if the drops themselves are flared out relative to a vertical centre line, the levers could in turn sit at or within the 10° inward angle rule relative to the drops but much more than that relative to that vertical centre line.
Sources indicate the UCI will now seek to close the latter of these two loopholes with a new minimum lever width at the hoods. The UCI is believed to be considering 32 cm for this lever width and if last year’s lever angle rule is anything to go by, it could be in place as early as January 1st. Some sources Escape spoke to supported such a move, indicating they believe too-narrow levers are a problem.
Others simply see it as more ineffective meddling from the UCI. “While I think they [the UCI] could tighten up the regs, it [bar width restrictions] would unfairly hurt smaller riders, unless they make bar width limitations based on height,” said a WorldTour coach.
Technically, it could be quick and easy for the UCI to govern such a rule with a simple chuck, similar to that used for checking cyclocross tyre widths. If the chuck fits, the setup is a pass, but if it’s too narrow and the chuck doesn’t fit, the rider has to change something.
Practically, though, with many levers now featuring an inward flare and with many bikes already built for next season, some with already-narrow lever positions, teams and manufacturers could be in a race to swap a considerable number of handlebars asap in order to give riders time to adjust to new positions before racing starts just weeks from now.
Too big = too fast?
The third strategy in the UCI’s current considerations seeks to introduce a restriction on chainring sizes. This is arguably the most contentious of the three; we couldn’t find a single source in favour of a gearing restriction, and everyone we spoke to argued it would be ineffective, unfair, and actually, potentially more dangerous.
“I think it will end some riders careers,” one WorldTour coach told Escape, pointing to published research that indicates the best cadence is a self selected cadence. The coach specifically highlighted sprinting, where riders “need to push against a bit of gear.” The coach’s argument circles on the belief that artificially increasing cadence with smaller gears (or decreasing cadence with bigger gears for that matter) will hamper some riders more than others and thus provide an unfair advantage.
The same sentiment was shared with others we spoke to, with another WorldTour source suggesting such an intervention will further tilt an already un-level playing field. “Every rider has an optimal pedaling frequency, and gear ratios relate that to ground speed,” said the source. “So riders with a naturally low pedaling frequency will be impacted moreso.” In simpler terms, gearing limits will limit gear munchers more than they will high cadence spinners.
“Gearing isn’t why speeds have increased (bar a small efficiency gain)” another source said, adding “speed isn’t the problem, and safety doesn’t come from limiting speed.” The source suggested the UCI should focus on safety interventions such as safer equipment, better bike handling, and safer courses, along with systems and protocols that enabled rapid medical response when crashes do happen. Those are topics we explored just a few weeks ago in our story about four things we believe the UCI must do now to improve safety.
Arguably, much of the perceived benefit of a gearing restriction stems from a misunderstanding of why professional riders and teams are using oversized chainrings in the first place. These giant chainrings, sometimes 60 teeth or more, are not employed simply to achieve bigger gears or as some magical way of unlocking more power.
Rather, they improve drivetrain efficiency by reducing chain tension (lower tension decreases frictional losses throughout the drivetrain, making the system more efficient) and reducing chain articulation (larger chainrings have a gentler curvature, meaning the chain bends less as it wraps around the chainring, which reduces friction and increases mechanical efficiency). It also reduces cross-chaining, another source of drivetrain friction. These differences are not large, but in a sport where seeking every possible gain is imperative, even small benefits are not left behind.
But the actual gear ratio used often remains largely the same. This is because when using a larger chainring, the rider often compensates by shifting to a larger rear sprocket to maintain their preferred cadence, as previously discussed. This adjustment means the overall gear ratio remains broadly the same. For example, a rider might switch from a 54×11 as their largest gear to a 60-tooth ring, but end up riding in a 60×13 combination, which delivers a similar gear ratio and cadence.
One scenario where this defense doesn’t ring true is on long, steep and less technical descents. In this example, the bigger the gear, the faster the rider can go before spinning out. In this case, might smaller gears effectively translate into a real cap on maximum speeds? Again, in theory that works, but the problem is those types of descents are very infrequent, and there are trade-offs elsewhere that might make racing less safe.
Take sprints, for example. On the face of it smaller gears could make for slower sprinting – a good thing for sprinting safety, one might assume. But that’s not the case, according to some sources, who argue that while sprinting speeds will remain high, riders will have to spin much faster cadences and thus add more instability into the entire bike and rider system, potentially leading to more crashes.
How would a gear limit even work – might we see junior gear-style roll-out checks introduced before stage starts at the Tour de France? Unlikely, but it is kind of ironic that having just dropped the junior gear size restrictions in recent years, citing science that dispelled the claimed benefits of imposing such restrictions, the UCI is now considering applying a similar approach to the world’s best riders.
Much more likely than a gear ratio limit is that the UCI simply caps the largest chainring size. Sources have told Escape it is their understanding major groupset manufacturers wouldn’t have to change the chainring combinations they currently offer, indicating perhaps a 54-tooth chainring or similar might become the new maximum permitted size. That approach could be extended to include a 9- or 10-tooth sprocket limit on the cassette also, but in all likelihood the drivetrain efficiency losses might mean any motivation to seek bigger ratios with smaller sprockets may not transpire anyway.
While the Shimanos and SRAMs of this world may be largely unaffected by such a change, imagine what such a chainring-cap rule would do to an independent chainring manufacturer, many of which have carved out small business opportunities in supplying the chainrings the larger brands don’t see the market demand to justify.
Again, Escape Collective contacted the UCI for comment on the proposals reportedly under consideration, but as of yet has not received a response. While we wait the sport and industry are both stuck in no man’s land, with riders, teams, and manufacturers all awaiting clarity on the implications for both competition and technology a matter of weeks out from the 2025 season. One thing is certain: the debate around these proposals has only just begun.
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