{
 "version": "2026-10-20",
 "license": "Dimension sheets: CC BY 4.0. Standard and published-size files: CC BY 4.0. Xem Studio's own designs (files_license = Xem Studio Design License): free to use and sell things from, not to redistribute as files — https://xemstudio.com/license/. Other publishers' files: their own license, linked beside them.",
 "slug": "caster",
 "name": "Caster angle",
 "kind": "standard",
 "category": "Car design",
 "group": "Suspension geometry",
 "year": null,
 "question": "What is caster and why do race cars and RC cars run so much of it?",
 "tags": [
  "vehicle design",
  "suspension geometry",
  "rc design",
  "aerodynamics"
 ],
 "aliases": [
  "caster",
  "castor",
  "caster angle",
  "rc caster block",
  "caster trail",
  "mechanical trail",
  "positive caster",
  "caster self centering",
  "c-hub caster",
  "how much caster",
  "caster vs camber"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/caster/",
 "sheet_txt": "https://xemstudio.com/objects/caster/sheet.txt",
 "sheet": {
  "basis": "Design rules and figures from the cited sources; example geometry by Xem Studio",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Caster is the side-view tilt of the steering axis. With positive caster the axis meets the road ahead of the contact patch, so the wheel trails and self-centres, improving directional stability (Wikipedia).",
   "More caster gives straight-line stability and camber gain when steering but heavier, less responsive steering (Wikipedia; Formula1-Dictionary). On RC cars, higher caster gives more stability and less off-power corner-entry steering (Tekno).",
   "Road cars commonly run over 7 deg with radial tyres; some F1 cars exceed 10 deg; RC buggies stack kick-up and caster-block angles to well over 20 deg.",
   "The file is a reference example built by Xem Studio from the numbers above (Reference 1/10 off-road: track 250 mm and 90 mm wheel+tyre (EFRA maxima); wheelbase illustrative.). Sizes the sources do not fix are illustrative; scale the example to your own vehicle."
  ],
  "table": {
   "columns": [
    "parameter",
    "value or range",
    "source"
   ],
   "rows": [
    [
     "Road cars (radial tyres)",
     "over 7 deg common",
     "Wikipedia"
    ],
    [
     "F1",
     "at least a few deg; some over 10 deg",
     "Formula1-Dictionary"
    ],
    [
     "FSAE example",
     "+2.923 deg front, mechanical trail 11.667 mm",
     "Univ. of Utah FSAE"
    ],
    [
     "RC total caster example",
     "11 deg kick-up + 0.5 deg insert + 15 deg block = 26.5 deg",
     "Tekno setup guide"
    ],
    [
     "RC caster blocks (C-hub)",
     "21, 18, 15 deg options",
     "Adrenaline RC"
    ]
   ]
  }
 },
 "sheet_text": "Caster angle — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/caster/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)\nBasis: Design rules and figures from the cited sources; example geometry by Xem Studio\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Caster is the side-view tilt of the steering axis. With positive caster the axis meets the road ahead of the contact patch, so the wheel trails and self-centres, improving directional stability (Wikipedia).\n- More caster gives straight-line stability and camber gain when steering but heavier, less responsive steering (Wikipedia; Formula1-Dictionary). On RC cars, higher caster gives more stability and less off-power corner-entry steering (Tekno).\n- Road cars commonly run over 7 deg with radial tyres; some F1 cars exceed 10 deg; RC buggies stack kick-up and caster-block angles to well over 20 deg.\n- The file is a reference example built by Xem Studio from the numbers above (Reference 1/10 off-road: track 250 mm and 90 mm wheel+tyre (EFRA maxima); wheelbase illustrative.). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.\n\nparameter  value or range  source\nRoad cars (radial tyres)  over 7 deg common  Wikipedia\nF1  at least a few deg; some over 10 deg  Formula1-Dictionary\nFSAE example  +2.923 deg front, mechanical trail 11.667 mm  Univ. of Utah FSAE\nRC total caster example  11 deg kick-up + 0.5 deg insert + 15 deg block = 26.5 deg  Tekno setup guide\nRC caster blocks (C-hub)  21, 18, 15 deg options  Adrenaline RC\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Wikipedia: Caster angle — web — Publisher's page; dimensions are facts — https://en.wikipedia.org/wiki/Caster_angle\n- Formula1-Dictionary: Castor angle — web — Publisher's page; dimensions are facts — https://formula1-dictionary.net/castor_angle.html\n- University of Utah, Mechanical Engineering: Formula SAE Suspension System (senior design) — web — Publisher's page; dimensions are facts — https://mech.utah.edu/wp-content/uploads/2024/12/5-Formula-SAE-Suspension.pdf\n- Tekno RC: Tekno RC Setup Guide — web — Publisher's page; dimensions are facts — https://teknoforums.com/misc/Tekno-RC-Setup-Guide.pdf\n- Adrenaline RC Racing: Mastering Caster & Kick-Up for Better Offroad RC Racing Performance — web — Publisher's page; dimensions are facts — https://www.adrenalinercracing.com/blogs/news/mastering-caster-kick-up-for-better-offroad-rc-racing-performance\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/caster/index.json\nAPI: https://xemstudio.com/api/geometry?object=caster\n",
 "sources": [
  {
   "publisher": "Wikipedia",
   "title": "Caster angle",
   "url": "https://en.wikipedia.org/wiki/Caster_angle",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Formula1-Dictionary",
   "title": "Castor angle",
   "url": "https://formula1-dictionary.net/castor_angle.html",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "University of Utah, Mechanical Engineering",
   "title": "Formula SAE Suspension System (senior design)",
   "url": "https://mech.utah.edu/wp-content/uploads/2024/12/5-Formula-SAE-Suspension.pdf",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Tekno RC",
   "title": "Tekno RC Setup Guide",
   "url": "https://teknoforums.com/misc/Tekno-RC-Setup-Guide.pdf",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Adrenaline RC Racing",
   "title": "Mastering Caster & Kick-Up for Better Offroad RC Racing Performance",
   "url": "https://www.adrenalinercracing.com/blogs/news/mastering-caster-kick-up-for-better-offroad-rc-racing-performance",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "camber",
  "kick-up",
  "toe-front",
  "toe-rear",
  "ackermann",
  "anti-ackermann"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no printing tolerance)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no printing tolerance. Where a part meets another part, the object lists its mating features (feature, exact size, what it mates with, fit class: press, slide, run, socket, clamp or designed). Apply your process's allowance to those features only; 'designed' gaps are part of the design and stay as drawn.",
 "mating": [],
 "faq": [
  {
   "q": "Why does caster add camber when steering?",
   "a": "Tilting the steering axis back makes the outside wheel lean in as it steers; racers use large caster for this camber gain (Wikipedia)."
  }
 ],
 "files_license": {
  "name": "Xem Studio Design License",
  "holder": "Xem Studio",
  "url": "https://xemstudio.com/license/",
  "note": "Xem Studio's own design: free to use, print, modify and sell things made from it; not to be republished or redistributed as files."
 },
 "offers": [
  {
   "file": "caster-geometry",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/caster/caster-geometry.step",
   "stl": "https://xemstudio.com/files/hardware/caster/caster-geometry.stl",
   "note": "Caster demo: steering axis tilted back 26.5°, wheelbase 260 mm, Ø90 tyres (illustrative layout)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/caster/index.md"
}