Sean Kelly Exposes the Terrifying Reality of Modern Pro Cycling: Deadly Brakes, Aero Bikes, and Monster Gears Turning Races Into Risky Battlegrounds
Sean Kelly, the Irish cycling legend, is no stranger to the rigors of professional cycling. Having spent over two decades in the sport, claiming victories in some of the world’s most grueling races, Kelly knows the risks that cyclists face on the road. However, in recent years, Kelly has raised concerns about a new wave of dangers infiltrating the peloton—dangers that are the byproducts of technological advancements meant to make riders faster but are instead turning races into perilous battlegrounds.
In interviews and commentary, Kelly has drawn attention to three major areas of concern: the widespread adoption of disc brakes, the rise of ultra-aero bikes, and the use of bigger, more aggressive gearing. These innovations, while improving performance, are adding unprecedented levels of danger, leading Kelly to believe that cycling’s modernization could be heading down a treacherous path.
Disc Brakes: A Cutting-Edge Weapon?
One of the most hotly debated topics in the pro cycling world over the last decade has been the introduction of disc brakes. Initially designed to provide better stopping power, especially in wet conditions, disc brakes have largely replaced traditional rim brakes. The argument for disc brakes is clear: they allow riders to brake more quickly and consistently, especially during high-speed descents and technical races. However, Sean Kelly warns that this apparent upgrade in safety comes with significant, and often overlooked, dangers.
Kelly is not alone in his criticism. Several riders and teams have voiced concerns about the risks posed by disc brakes, particularly when crashes occur. Unlike rim brakes, which apply pressure to the outer wheel, disc brakes function via rotors attached to the hub of the wheel. These rotors, often made from sharp-edged metal, can become dangerously exposed during crashes.
“There’s no doubt they stop better, but in a crash situation, those discs can act like blades,” Kelly explained in a recent interview. “You have riders going down at high speeds, and you have these exposed discs that can cause serious injuries. We’ve seen it happen already, and it’s frightening.”
Incidents of riders sustaining deep cuts from disc brakes have been reported. In 2016, during the Paris-Roubaix race, Spanish rider Francisco Ventoso suffered a gruesome leg injury after a crash involving disc brakes. The injury, which required surgery, sparked renewed debate over their safety. Kelly himself has highlighted that the speed at which disc brakes stop a bike can cause unexpected accidents, as they allow for much sharper braking than what riders using rim brakes might expect.
For Kelly, the question isn’t whether disc brakes are more efficient—they undoubtedly are—but whether the sport has sufficiently accounted for the dangers they introduce. In high-stakes races, where hundreds of riders are often packed tightly together at high speeds, even the smallest miscalculation can have catastrophic consequences.
Aero Bikes: Speed at Any Cost
If disc brakes are a contentious addition to cycling, the rise of aero bikes might be even more so. Designed to maximize aerodynamic efficiency, these bikes are the culmination of years of wind-tunnel testing and engineering. Every tube, every angle, and every component is sculpted to reduce drag, helping riders cut through the wind with greater speed. However, Sean Kelly believes these bikes are pushing the limits of safety.
“Aero bikes are fantastic in theory,” Kelly said. “They help riders save watts and can make a huge difference over a long race. But the issue is that these bikes are becoming harder to handle, especially in real-world conditions like strong winds, technical descents, or cobbled roads.”
Kelly isn’t exaggerating the challenges posed by these super-aero machines. As the pursuit of speed has pushed bike manufacturers to design ever-more radical frames, the geometry of aero bikes has become increasingly aggressive. Many of these bikes feature narrow head tubes, integrated handlebars, and deep-section wheels—all designed to slice through the air but with the downside of reducing stability.
The effects are particularly evident in crosswinds. Aero bikes, with their deeper profiles, are more susceptible to being buffeted by strong gusts, making it more challenging for riders to maintain control. This is especially dangerous during descents or in the chaotic final kilometers of a race, where riders are jockeying for position.
Kelly, who was known for his incredible bike-handling skills during his career, noted that many modern riders are not being properly trained to handle these machines. “Back in my day, we spent hours learning how to control the bike in all sorts of conditions,” he recalled. “Now, everything is focused on aerodynamics, but if you can’t control the bike, it doesn’t matter how fast it is.”
The demand for faster, more efficient bikes has led to a culture where aero gains often trump safety considerations. With races becoming faster and more intense, Kelly fears that the obsession with speed could lead to more crashes and injuries in the peloton.
Monster Gears: Power at a Price
One of the more subtle yet profound changes in modern cycling has been the increase in gear ratios. Riders are now using much larger chainrings, often going up to 54 or even 56 teeth on the front chainring, coupled with smaller sprockets on the rear cassette. These “monster gears” allow riders to push higher speeds, especially on flatter stages or time trials, but they come at a significant physical cost.
Kelly has pointed out that the shift toward larger gears is part of a broader trend in cycling—one that prioritizes raw power over finesse and endurance. While it’s true that today’s riders are stronger, more aerodynamic, and better supported by sports science than ever before, the physiological demands of pushing such big gears can lead to increased strain and fatigue.
“We used to race with much smaller gears, and it allowed us to have more control over our cadence,” Kelly explained. “Now, with these huge gears, riders are putting a lot more stress on their muscles and joints. Over time, this leads to more injuries, particularly in the knees and lower back.”
Kelly’s concerns are echoed by sports physiologists who have studied the impact of gearing on rider performance and injury risk. While larger gears can provide a performance edge, particularly in time trials or sprint finishes, they require greater force to turn, which can place excessive pressure on the body. For riders who race over 100 days a year, this can lead to chronic injuries and long-term damage.
Additionally, the use of larger gears has changed the dynamics of racing. With riders able to maintain higher speeds over long distances, the peloton is often stretched to its limits. This has led to more aggressive racing, with fewer opportunities for recovery, making crashes and mechanical failures more likely.
The Battle for Speed: A Double-Edged Sword
What makes Kelly’s critique so important is his perspective as someone who has seen cycling evolve from its “heroic” era to its modern, hyper-technical incarnation. Kelly competed in a time when racing was as much about strategy and endurance as it was about speed. He won Paris-Roubaix twice, a race known for its brutal cobblestones and technical difficulty, relying on bike handling and tactical acumen to outlast his competitors.
Today, Kelly sees a sport increasingly driven by data, technology, and marginal gains. While there is no doubt that modern cycling is faster and more competitive than ever, Kelly argues that the balance between performance and safety has been lost. Riders are now expected to navigate faster bikes, more aggressive gearing, and more dangerous braking systems, all while racing in pelotons that are larger and more tightly packed than in previous eras.
Cycling has always been a dangerous sport. Crashes, injuries, and even fatalities have been a part of the sport’s history since its inception. However, Kelly’s warnings about the modern era suggest that the risks are being amplified by a relentless pursuit of speed at all costs.
As the sport continues to evolve, the questions Kelly raises will need to be addressed. Should race organizers and governing bodies impose stricter regulations on the use of technology? Should teams prioritize rider safety over performance? Or will the pursuit of speed ultimately turn cycling into a sport where danger is an accepted part of the spectacle?
Kelly, for his part, hopes that cycling will find a way to balance innovation with safety. “Technology is fantastic, and it’s helped push the sport forward,” he said. “But at the end of the day, we need to make sure that we’re not sacrificing the safety of the riders in the process. Otherwise, we’re going to see more accidents, more injuries, and possibly more tragedies.”
As cycling hurtles toward a faster, more dangerous future, it’s clear that the stakes have never been higher.
