Dedicated Subsystem WorkbenchPlatform Gen: 2018–2024

2020 Yamaha YZ450F Motocross Valve Clearance Specs & Shim Calculator

Cold valve clearance specs for 2020 Yamaha YZ450F Motocross: intake mm, exhaust mm, inspection intervals and replacement shim calculator.

Gen 2018–2024

Factory Platform Compatibility: All workshop fluid capacities, maintenance milestones, torque specifications, and consumables on this specification sheet are factory-identical across model years 2018 through 2024.

Select Model Year:(Active: 2020)

2018 2019 2020 2021 2022 2023 2024

Engine

450cc

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)

1. Feeler Gauge Measured Clearance (mm)

Factory intake tolerance: 0.10 - 0.20 mm

2. Currently Installed Shim (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

0 Open Campaigns (Clean)

U.S. Department of Transportation compliance database (Title 49 U.S.C. Chapter 301).

Verify VIN on NHTSA.gov

No Active Federal Safety Recalls Reported

The U.S. DOT National Highway Traffic Safety Administration (NHTSA) records zero open safety recall campaigns for the 2020 Yamaha YZ450F Motocross platform. Always check your individual 17-digit VIN at an authorized dealership or via NHTSA.gov for individual recall completions.