{
 "name": "Bicycle chain wear replacement thresholds, as makers publish them",
 "description": "The chain wear (elongation) point at which Park Tool, SRAM and Shimano say to replace a bicycle chain, by drivetrain (single-speed, 10-speed or less, 11-speed or more, SRAM, Shimano), in each publisher’s own wording. threshold_pct is empty where the publisher gives no percentage (Shimano publishes a gauge only). Every row links the publisher’s page and the date it was checked.",
 "url": "https://pedalbrief.com/data/chain-wear-thresholds",
 "license": "https://creativecommons.org/licenses/by/4.0/",
 "attribution": "Pedal Brief (pedalbrief.com)",
 "citation": "Pedal Brief (pedalbrief.com), “Bicycle chain wear replacement thresholds, as makers publish them”, https://pedalbrief.com/data/chain-wear-thresholds, CC BY 4.0. Sources checked 11 Oct 2026.",
 "notice": "Compilation by Pedal Brief under CC BY 4.0. The underlying facts come from the sources linked in each row; brand and team names and trademarks belong to their owners. Provided as is, without warranty.",
 "used_on": "https://pedalbrief.com/tools/chain-wear",
 "date_modified": "2026-10-18",
 "oldest_check": "2026-10-11",
 "fields": [
  {
   "name": "publisher",
   "type": "text",
   "description": "Who publishes the threshold"
  },
  {
   "name": "source_title",
   "type": "text",
   "description": "Title of the page or document"
  },
  {
   "name": "scope",
   "type": "text",
   "description": "Chains the threshold applies to"
  },
  {
   "name": "drivetrains",
   "type": "text",
   "description": "Drivetrain groups the row covers (several separated by \" | \")"
  },
  {
   "name": "threshold_pct",
   "type": "number",
   "description": "Replacement point in % elongation; empty if not published"
  },
  {
   "name": "wording",
   "type": "text",
   "description": "The publisher’s wording"
  },
  {
   "name": "source_url",
   "type": "url",
   "description": "Source page"
  },
  {
   "name": "checked",
   "type": "date",
   "description": "Date Pedal Brief checked the source"
  }
 ],
 "row_count": 9,
 "rows": [
  {
   "publisher": "Park Tool",
   "source_title": "When to Replace a Worn Chain",
   "scope": "Single-speed",
   "drivetrains": "Single-speed",
   "threshold_pct": 1.0,
   "wording": "Replace by the time it reaches 1.0% wear",
   "source_url": "https://www.parktool.com/en-us/blog/repair-help/when-to-replace-a-chain-on-a-bicycle",
   "checked": "2026-10-11"
  },
  {
   "publisher": "Park Tool",
   "source_title": "When to Replace a Worn Chain",
   "scope": "10-speed cassette/freewheel or less",
   "drivetrains": "10-speed or less",
   "threshold_pct": 0.75,
   "wording": "Replace by the time it reaches 0.75% wear",
   "source_url": "https://www.parktool.com/en-us/blog/repair-help/when-to-replace-a-chain-on-a-bicycle",
   "checked": "2026-10-11"
  },
  {
   "publisher": "Park Tool",
   "source_title": "When to Replace a Worn Chain",
   "scope": "11-speed cassette or more",
   "drivetrains": "11-speed or more",
   "threshold_pct": 0.5,
   "wording": "Replace by the time it reaches 0.5% wear",
   "source_url": "https://www.parktool.com/en-us/blog/repair-help/when-to-replace-a-chain-on-a-bicycle",
   "checked": "2026-10-11"
  },
  {
   "publisher": "Park Tool CC-3.2",
   "source_title": "CC-3.2 Chain Wear Indicator",
   "scope": "5-to-10-speed chains",
   "drivetrains": "10-speed or less",
   "threshold_pct": 0.75,
   "wording": "Replace at or just before 0.75%",
   "source_url": "https://www.parktool.com/en-us/product/chain-wear-indicator-cc-3-2",
   "checked": "2026-10-11"
  },
  {
   "publisher": "Park Tool CC-3.2",
   "source_title": "CC-3.2 Chain Wear Indicator",
   "scope": "11-to-12-speed chains",
   "drivetrains": "11-speed or more",
   "threshold_pct": 0.5,
   "wording": "Replace at or just before 0.5%",
   "source_url": "https://www.parktool.com/en-us/product/chain-wear-indicator-cc-3-2",
   "checked": "2026-10-11"
  },
  {
   "publisher": "Park Tool CC-3.2",
   "source_title": "CC-3.2 Chain Wear Indicator",
   "scope": "SRAM Flattop / T-Type 12-speed",
   "drivetrains": "SRAM",
   "threshold_pct": null,
   "wording": "Use the CC-4.2 for SRAM Flattop and SRAM T-Type 12-speed chains",
   "source_url": "https://www.parktool.com/en-us/product/chain-wear-indicator-cc-3-2",
   "checked": "2026-10-11"
  },
  {
   "publisher": "Park Tool CC-4.2",
   "source_title": "CC-4.2 instructions",
   "scope": "5-to-12-speed, including irregular roller sizes",
   "drivetrains": "Single-speed | 10-speed or less | 11-speed or more | SRAM",
   "threshold_pct": null,
   "wording": "Go/no-go gauge for 0.5%, 0.75% and 1% wear (points at which most manufacturers suggest replacement)",
   "source_url": "https://www.parktool.com/assets/doc/product/CC-4.2_instructions.pdf",
   "checked": "2026-10-11"
  },
  {
   "publisher": "SRAM",
   "source_title": "When should I replace my SRAM Eagle chain?",
   "scope": "SRAM Eagle (0.8% wear critical on TL-CNTL-WEAR-A1)",
   "drivetrains": "SRAM",
   "threshold_pct": 0.8,
   "wording": "Replace the chain when it reaches 0.8% on an approved chain checker",
   "source_url": "https://support.sram.com/hc/en-us/articles/5928711817755-When-should-I-replace-my-SRAM-Eagle-chain",
   "checked": "2026-10-11"
  },
  {
   "publisher": "Shimano",
   "source_title": "How to Check Your Chain Length",
   "scope": "SHIMANO chains (TL-CN42). No public elongation % published",
   "drivetrains": "Shimano",
   "threshold_pct": null,
   "wording": "Use a SHIMANO chain gauge; replace when the teeth of the gauge completely fall into the chain",
   "source_url": "https://bike.shimano.com/en-UK/stories/article/determine-chain-length.html",
   "checked": "2026-10-11"
  }
 ]
}