Chain wear replacement thresholds
Makers' own published wear bands, side by side. Pick a drivetrain, optionally enter an elongation %, get a go/no-go.
Published thresholds
| Publisher | Applies to | Threshold | Source |
|---|---|---|---|
| Park Tool | Single-speed | 1.0% | When to Replace a Worn Chain |
| Park Tool | 10-speed cassette/freewheel or less | 0.75% | When to Replace a Worn Chain |
| Park Tool | 11-speed cassette or more | 0.5% | When to Replace a Worn Chain |
| Park Tool CC-3.2 | 5-to-10-speed chains | 0.75% | CC-3.2 Chain Wear Indicator |
| Park Tool CC-3.2 | 11-to-12-speed chains | 0.5% | CC-3.2 Chain Wear Indicator |
| Park Tool CC-3.2 | SRAM Flattop / T-Type 12-speed | — | CC-3.2 Chain Wear Indicator |
| Park Tool CC-4.2 | 5-to-12-speed, including irregular roller sizes | — | CC-4.2 instructions |
| SRAM | SRAM Eagle (0.8% wear critical on TL-CNTL-WEAR-A1) | 0.8% | When should I replace my SRAM Eagle chain? |
| Shimano | SHIMANO chains (TL-CN42). No public elongation % published | — | How to Check Your Chain Length |
How to measure
- Ruler (ballpark)Line up a rivet at the zero mark. Count 24 more rivets; the last should sit at the 12″ mark. Off by more than 1/16″ → replacement point. Source
- Park Tool CC-3.2Hook on a roller between inner plates. If the 0.5% tip inserts, the chain is at least 0.5% longer; flip for 0.75%. Source
- Park Tool CC-4.2Lower onto the chain, keep tension on the short section, then push the chain onto the gauge tip. Reads 0.5%, 0.75% and 1%. Source
0.8% wear critical; compatible with HARD CHROME and non-HARD CHROME SRAM chains SRAM Chain Wear Indicator TL-CNTL-WEAR-A1.
Sizing a new chain? Chain length Derailleur capacity
Contact the chain manufacturer for specific replacement recommendations. Not our advice, and not merged. Sources checked 11 Oct 2026: Park Tool; Park Tool CC-3.2; Park Tool CC-4.2; SRAM; Shimano; Park Tool CC-3.2; SRAM Chain Wear Indicator TL-CNTL-WEAR-A1.
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