How Do You Measure Chain Stay?

Measuring chainstay length involves determining a specific distance on your bicycle frame. The chainstay length is the straight-line distance between the centre of the bottom bracket axle and the centre of the rear dropout, so it's fairly easy to measure with a ruler.

What is Chainstay Length?

The chainstay is a tube or set of tubes that connects the bottom bracket shell (where the crankset attaches) to the rear dropout (where the rear wheel axle sits). The length of the chainstay is a critical frame dimension that significantly impacts a bicycle's handling characteristics and capabilities. As mentioned in the reference, it is the straight-line distance between two specific points on the frame.

Step-by-Step Measurement Guide

Measuring chainstay length is straightforward and, as the reference notes, can be done with simple tools like a ruler or tape measure.

1. Locate the Bottom Bracket Centre: Identify the center of the spindle that passes through the bottom bracket shell. This is the pivot point for your cranks.
2. Locate the Rear Dropout Centre: Find the centre point of the rear axle slot or hole in the rear dropout where the rear wheel attaches.
3. Measure the Straight-Line Distance: Using a ruler or measuring tape, measure the direct, straight-line distance between the center of the bottom bracket axle and the center of the rear dropout.
4. Record the Measurement: Note down the measurement, typically in millimeters (mm) or centimeters (cm).

For accuracy, ensure the measurement tool is held straight and level between the two points.

Why Chainstay Length Matters

Chainstay length is a fundamental aspect of bicycle frame geometry. It plays a significant role in how a bike rides and handles.

Key Influences of Chainstay Length:

• Handling: Shorter chainstays generally result in a more agile, quick-handling bike, often easier to manual or lift the front wheel. Longer chainstays tend to provide more stability, especially at speed or when climbing.
• Tire Clearance: The length of the chainstays dictates how much space is available between the seat tube and the rear tire, affecting the maximum tire width you can fit.
• Weight Distribution: Chainstay length influences the rider's weight distribution relative to the rear wheel, impacting traction, climbing ability, and balance.
• Wheelbase: Along with the front-center (distance from bottom bracket to front axle), chainstay length contributes to the bike's overall wheelbase.

Measuring your chainstay length allows you to understand one of the key design elements of your bike and how it contributes to its performance characteristics.