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BBR - CRF/XR50 18mm Big Carb Kit for Stock Head

Vital Information
Part No 420-HXR-5003
Stock Level Out of Stock!
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Lever up = Choke on
Lever down = Choke off
Air filter size needed: 1.25 inches

Perfect add-on for our big bore kits and exhaust systems. Increase power throughout the RPM range. Includes all required hardware for easy installation right down to a jet assortment for fine tuning.

Kit Includes:

  • 421-BBR-2001 - BBR 18mm carb
  • 510-HXR-5103 - BBR throttle
  • 512-BBR-1001 - BBR throttle cable
  • 421-KEH-3002 - BBR jet kit 5 main jets and 3 pilot jets
  • TBW0263 - TBparts manifold for the STOCK CRF/XR50 head, Includes gaskets and bolts

  • Air filter - UNI-UP-4125AST
  • Uni air filter spray - W-82-1000
  • BBR jet kit - 421-KEH-3001
  • Carb repair kit - 421-KEH-9001
  • Pre-filter - WHS-1664


  • CRF50 - 2000-Present
  • XR50 - 2000-Present
Application Note: This 18mm Carb Kit is not recommended for use on stock displacement CRF50's. Recommended for 82cc or larger displacement motors.

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