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Dedicated Subsystem WorkbenchPlatform Gen: 20212026

2021 Honda CRF300L Valve Clearance Specs & Shim Calculator

Cold valve clearance specs for 2021 Honda CRF300L: intake mm, exhaust mm, inspection intervals and replacement shim calculator.

Gen 20212026

Factory Platform Compatibility: All workshop fluid capacities, maintenance milestones, torque specifications, and consumables on this specification sheet are factory-identical across model years 2021 through 2026.

Select Model Year:(Active: 2021)
Engine
286cc
Drive
520
Cooling
Liquid-Cooled

Factory Valve Clearance & Shim Calculator

OEM Workshop Tolerances
Cylinder head valve lash specifications, timing TDC mark alignments, and interactive replacement shim calculation engine.
Adjustment Mechanism: 7.48 mm
Active Valve Range (INTAKE)
0.10 - 0.20 mm
0.004 - 0.008 in
Nominal Mid-Spec Target
0.15 mm
Ideal cold lash assembly setting
Shim Diameter / Tappet
7.48 mm
Bucket-and-shim interface
Measurement Condition
Cold Engine (≤ 35°C / 95°F)
TDC compression stroke only
Interactive Shim Sizing Calculation Engine: New Shim = Current Shim + (Measured Clearance - Target Clearance)
mm
Factory intake tolerance: 0.10 - 0.20 mm
mm
Measured with micrometer or read laser-etched face
TDC Crankshaft Timing Index
Align crankshaft TDC mark with engine timing index pointer
Feeler Gauge Technique
Angled stainless steel feeler gauge (cold engine ≤ 35°C / 95°F)

Official NHTSA Safety Recalls & Technical Bulletins

1 Active Campaign
U.S. Department of Transportation compliance database (Title 49 U.S.C. Chapter 301).
Verify VIN on NHTSA.gov
The U.S. National Highway Traffic Safety Administration reports 1 safety recall campaign associated with this platform. Independent repair shops and riders should confirm that authorized dealership warranty remedies have been applied.
NHTSA #21V382000EXTERIOR LIGHTING
Received: 24/05/2021
Defect Description

Honda (American Honda Motor Co.) is recalling certain 2020-2021 Super Cub C125, CB500X, CB650R, CBR300R, CBR500R, CBR650R, Rebel 300, Rebel 500, Monkey, 2020 CRF250L, GROM, 2021 CRF300L, and CB500F motorcycles. The rear reflector lens may not reflect brightly enough. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 108, "Lamps, Reflective Devices, and Associated Equipment."

Safety Hazard / Consequence

A dim rear reflector may reduce the visibility of the motorcycle to other drivers, increasing the risk of a crash or injury.

Factory Remedy & Repair Action

Dealers will replace the rear reflector, free of charge. Owner notification letters were mailed July 7, 2021. Owners may contact Honda customer service at 1-866-784-1870. Honda's number for this recall is KM3.

Manufacturer Notes: Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.

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2021 Honda CRF300L Valve Clearance Specs & Shim Size Calculator | WowShopper Workshop | WowShopper Motorsports