The Burley Coho quick release bicycle hitch requires you to determine the correct axle length of your bicycle to ensure a proper fit. Here is a step-by-step guide to taking the necessary measurements:

### Step 1: Measure the length of the axle

1. **Remove the wheel from the bicycle:** Place the bicycle on a stand or lay it on its side so that you can easily access the axle.
2. **Measure the total length of the axle:** Use a caliper or tape measure to measure the entire length of the axle from one end to the other. Record this measurement.

### Step 2: Measure the total width of the outside of the frame

1. **Measure the mounting width of the rear hub (O.L.D. - Over Locknut Dimension):** This is the distance between the insides of the rear forks where the axle falls. Use a caliper to measure the distance between the inside edges of the rear fork dropouts. This measurement must be accurate because it determines whether the quick release will fit properly.
2. **Measure the outer width of the chainstay:** Now measure the total width of the outside of the chainstay, from the outside of the left fork to the outside of the right fork.

### Tips for accurate measurements

- **Use an accurate measuring tool:** A digital caliper can be useful for precise measurements.
- **Check both measurements:** Double check the measured values to ensure you have the correct measurements.
- **Note the values clearly:** Note both the axle length and the overall width of the frame to ensure you purchase the correct quick release.

With these measurements you can choose the right Burley Coho quick release bicycle coupling that fits your bike perfectly. It is important that these measurements are correct to ensure a safe and secure attachment of the trailer to your bicycle.