Fitting a bike can initially seem complex, especially when considering frame, handlebar, and saddle geometries. To simplify this, we can disregard these complexities and focus on measurements relative to the bottom bracket. This approach ensures that your hand position, the ultimate point of contact and control, is correctly positioned.
To begin, on your current bike, measure the horizontal distance from the center of the bottom bracket to where your hands comfortably rest on the handlebars. This measurement defines your reach. It’s important to measure to your hand position, not just the stem’s end, as handlebar variations significantly impact hand placement relative to the bottom bracket.
Next, determine the vertical difference. Measure from the center of the bottom bracket to the top of your handlebars at your hand position. A practical method involves measuring the distance from the floor to your bottom bracket and then from the floor to your handlebars. Subtracting the bottom bracket height from the handlebar height gives you the stack.
When transferring these measurements to a new bike, the goal is to replicate your stack and reach values as closely as possible. Adjust the new bike’s components—stem height, handlebar position, and potentially spacers—until these measurements match your original bike. Accurate stack and reach are fundamental for a comfortable and efficient riding posture.
Saddle height is straightforward to replicate. Assuming you use the same pedals, shoes, and crank length, your saddle height will remain consistent across bikes. However, saddle setback presents more of a challenge due to varying saddle lengths and individual preferences. A practical approach to setting saddle setback is to measure the horizontal distance from the back of your saddle to your hand position on your source bike. Transfer this measurement to your new bike after establishing stack, reach, and saddle height. This method provides a good starting point for saddle setback, after which you can fine-tune based on your comfort and riding style.
By focusing on these key measurements—reach, stack, saddle height, and saddle setback—relative to the bottom bracket, you can effectively Fit A Bike and ensure a comfortable transition between different bicycles. This method simplifies the bike fitting process and prioritizes the most crucial contact points for optimal cycling performance.
