How to Check for Chain Wear

By : Mr Mamil
Updated :

This article discusses how to check for chain wear on 10, 11, and 12-speed road bike chains.

Why measure the chain wear?

The chain is often the cheapest drivetrain component to replace. It’s a good practice to regularly check and replace the chain just before it wears out. A worn-out chain will accelerate the wear of the cogs and chainring.

How often should I measure for chain wear?

You can check for chain wear every 1,000 miles (1,600km) when it’s new. As the chain gets more wear, check at a shorter interval.

What factors affect chain wear?

The factors that affect chain wear include riding on flats vs hills, dry vs wet riding conditions, power, and torque generated, and regular cleaning, degreasing, and keeping the chain well-lubed.

Keep in mind that each rider will wear out their chain at a different rate. For example, a professional cyclist can wear out their chain in less than 1,500 miles while an amateur cyclist up to 4,000 miles. A waxed chain will start to wear out after 5,000 miles.

Should I get a chain checker tool?

Yes, it’s highly recommended to get a chain checker and a high-quality one to go with it. Many bike shops rely on the precision of Park Tool’s chain checkers such as the Park Tool CC-3.2 (cheapest), CC-4, or CC-2 (most expensive).

Method 1 – Using a chain checker

Park Tool CC-2 Chain Checker at 0.25 Reading for A New Chain
Park Tool CC-2 Chain Checker at 0.25 Reading for A New Chain

This is the most accurate way to measure a chain as the results can be quantified. There are many models of chain checkers available today.

You’ll see 0.5 and 0.75 printed on the chain checker. They represent a 0.50% wear and 0.75% wear respectively. It means that the chain is now 0.50% (or 0.75%) longer than originally.

For 10-speed chains, replace the chain when the reading nears 0.75%.

For 11 and 12-speed chains, replace the chain when the reading is between 0.50% and 0.75%.

  1. Insert the hook end into a chain link.
  2. Insert the other end with 0.5 into another chain link.
  3. If the 0.5 end doesn’t fit into the chain link, then the chain is not yet 0.50% worn.
  4. If the 0.5 end fits, then swap to the 0.75 end.
  5. If the 0.75 end doesn’t fit, then the chain is between 0.50% and 0.75% worn.
  6. If the 0.75 end fits, then the chain is 0.75% worn.

Method 2 – Lifting the chain

Lift the Chain from the Front Chainring
Lift the Chain from the Front Chainring

This is the easiest method to check for wear without needing any tools. While not being 100% accurate, it’s a good starting point to know how much the chain has worn.

  1. Shift to the smallest rear cog and largest front ring.
  2. At the 2 o’clock position on the front ring, lift off the chain with two fingers.
  3. If there’s a noticeable gap between the chain and chainring (ie : 0.5mm or more), then it’s about time to replace the chain.

Method 3 – Using a ruler

The ruler provides a ballpark measurement for chain wear.

  1. Shift to the smallest rear cog and largest front ring.
  2. Pick a rivet and line it up with the 0” mark.
  3. Count 24 more rivets and the 24th rivet should be at the 12” mark on the ruler.
  4. If it’s off by more than 1/16” (0.0625”), then the chain needs to be replaced.