Why the Pros Are Ditching 175mm Cranks for 165mm With INEOS's Phil Burt
Feb 7, 2025
auto_awesome
Join renowned physiotherapist Phil Burt, who has worked with Team Sky and guided Sir Bradley Wiggins to Olympic gold, as he unpacks the shift from 175mm to 165mm crank lengths in professional cycling. Discover the science behind this trend—shorter cranks enhance torque and cadence while reducing knee pain. Phil explains essential bike fit adjustments needed for comfort and performance. He also dives into the challenges faced by ultra-endurance cyclists and the importance of personalized bike setups to prevent discomfort—all while keeping your ride efficient!
The shift from 175mm to 165mm cranks reflects a broader trend that enhances cycling power and performance across all rider levels, not just the pros.
Proper bike fit adjustments, including saddle height and positioning, are critical when switching to shorter cranks to avoid discomfort and optimize efficiency.
Deep dives
The Shift from Long to Short Cranks
The trend in cycling is shifting from traditional 175mm cranks to shorter 165mm cranks, as evidenced by their adoption by Tour de France champions and top gravel riders. Shorter cranks make it easier for cyclists to maintain power and improved positions, especially in aggressive postures like time trials. Philbert explains that bike fit adjustments are crucial when transitioning to shorter cranks to avoid comfort and efficiency losses. He highlights how reducing crank length can enhance hip mobility, ultimately leading to better performance and endurance cycling.
Importance of Proper Bike Fit Adjustments
Philbert emphasizes the need for three key adjustments to bike fit when switching crank lengths to optimize performance. First, the saddle height must be raised to maintain proper leg extension; as the crank length decreases, the saddle position needs to be modified accordingly. Additionally, forward saddle position adjustments are necessary to keep the hips aligned over the bottom bracket, thus maximizing power output. Lastly, ignoring these fit adjustments may lead to pain and decreased energy efficiency, with many cyclists unaware of how poor fitting can impede their cycling performance.
Understanding Power and Cadence Dynamics
The biomechanical relationship between crank length and cycling cadence suggests that shorter cranks can enhance overall cycling efficiency. When using shorter cranks, cyclists may exert similar power while allowing for a higher cadence due to the smaller lever length. This dynamic change necessitates a shift to harder gears to stabilize the overall RPM, facilitating more efficient energy output. Philbert illustrates this with examples, noting that reduced crank lengths help stabilize the hips and decrease lateral movement, which in turn contributes to producing consistent power.
The Role of Proper Setup in Preventing Common Issues
Common cycling ailments like knee pain, lower back pain, and numb hands often stem from improper bike setups rather than inherent issues with the cyclist's body. Philbert points out that many riders might experience discomfort due to inadequate saddle height or position, leading to poor power application and increased strain on specific joints. He advises cyclists to prioritize their bike fit to optimize comfort and performance, as correct adjustments can significantly alleviate discomfort. For unrealized pain reasons, understanding the complex relationship between bike adjustments and body mechanics is essential for both elite athletes and recreational riders.
For decades, 175mm cranks were the go-to choice in the pro peloton. But now, from Tour de France champions to elite gravel racers, the shift to 165mm is in full swing.
To understand the science behind this trend, we sat down with Phil Burt—renowned physiotherapist for Team Sky, Ineos, and British Cycling. He’s the expert who helped guide Sir Bradley Wiggins to Olympic gold, and today, he’s here to explain why shorter cranks aren’t just for the pros anymore.
But making the switch isn’t as simple as swapping crank arms. Phil breaks down the three essential bike fit adjustments you need to get right—because without them, you could be sacrificing speed, comfort, and efficiency.
For amazing cycling kit go check out LeCol at www.lecol.cc Use code roadman20 to get 20% off your LeCol order