How To Measure Chain Slack

In the world of cycling, motorcycling, and machine maintenance, measuring chain slack is a crucial aspect of ensuring proper functionality. Chain slack refers to the degree of looseness or tightness of a chain and understanding how to measure it helps in extending the life of your machine. In this blog post, we’ll take you through a step-by-step guide on how to easily measure chain slack.

Tools You Need

To measure chain slack, you’ll need:

  1. A ruler or measuring tape
  2. Marker or chalk
  3. A clean piece of cloth

Steps to Measure Chain Slack

1. Position the Machine

Start by positioning your machine on a flat and stable surface. For bikes, it’s best to place them on their side stands.

2. Locate the Midway Point

Next, locate the midway point between the front and rear sprockets. This is the best point to measure chain slack. Use the marker or chalk to mark this point for easy visibility.

3. Clean and Inspect the Chain

Before you start measuring, clean the chain with the cloth to remove any dirt or grease. This makes the measurements more accurate. Also, visually inspect the chain for any signs of wear or damage.

4. Measure the Slack

Now that you’ve prepared, it’s time to measure the chain slack. Using your ruler or measuring tape:

Step 1: Push the chain upward as far as it can go and measure the distance from the center of the chain rivet to the marked point.
Step 2: Then, push the chain downward as far as it can go and measure the distance from the center of the chain rivet to the marked point.
Step 3: Subtract the first measurement from the second to get the total chain slack.

In most cases, the ideal chain slack for bikes is usually between 1 to 1.5 inches or 25 to 30 mm. However, it’s always best to refer to your machine’s manual for the manufacturer’s recommended chain slack.


There you have it – a simple guide on how to measure chain slack. Remember that maintaining the right chain slack is vital for the longevity and safety of your machine. Keep checking and adjusting your chain slack regularly to keep your machine performing at its best.