The Garage

Motocross

Stock-size parts in stock at MotoSport

Yamaha YZ450F 2025

Motocross, 450cc 4T

Partly verified

Illustration: a Yamaha motocross bike, not this exact model.

No CPSC recall found for the 2025 Yamaha YZ450F, checked 2026-10-15. Recalls

Spec card PDF

Wheels and tires

2 of 4 filled

Front rim
Not yet verified
Rear rim
Not yet verified
Front tire
80/100-21
Research level: Spec sheet (research) · checked 2026-09-25 source [1]
Rear tire
120/80-19
Research level: Spec sheet (research) · checked 2026-09-25 source [1]

Suspension

3 of 7 filled

Fork
KYB spring-type fork
Research level: Spec sheet (research) · checked 2026-09-25 source [1]
Fork travel
12.2-in (≈ 310 mm, converted by MotoXSports)
Research level: Spec sheet (research) · converted from 12.2-in · checked 2026-09-25 source [1]
Shock travel
12.4-in (≈ 315 mm, converted by MotoXSports)
Research level: Spec sheet (research) · converted from 12.4-in · checked 2026-09-25 source [1]
Stock fork spring rate
Not yet verified
Stock shock spring rate
Not yet verified
Static sag, bike only
Not yet verified
Race sag, rider on
Not yet verified

Fluids and capacities

1 of 4 filled

Engine oil spec
Not yet verified
Engine oil capacity
Not yet verified
Coolant capacity
Not yet verified
Fuel capacity
1.6 gal (≈ 6.1 L, converted by MotoXSports)
Research level: Spec sheet (research) · converted from 1.6 gal · checked 2026-09-25 source [1]

Dimensions

3 of 3 filled

Seat height
38.0 in (≈ 965 mm, converted by MotoXSports)
Research level: Spec sheet (research) · converted from 38.0 in · checked 2026-09-25 source [1]
Wheelbase
58.3 in (≈ 1481 mm, converted by MotoXSports)
Research level: Spec sheet (research) · converted from 58.3 in · checked 2026-09-25 source [1]
Weight
240 lbs (≈ 108.9 kg, converted by MotoXSports)
Research level: Spec sheet (research) · converted from 240 lbs · checked 2026-09-25 source [1]

Gearing

0 of 5 filled

Stock front sprocket, stock rear sprocket, chain pitch, stock chain links, stock final drive ratio
Not yet verified

Service specs

0 of 6 filled

Fork oil, brake fluid, coolant type, fuel octane, idle speed, valve clearance
Not yet verified
Solid marks are owner's-manual pages; hollow marks are manufacturer web or spec-sheet figures still waiting on a manual page. Last reviewed 2026-09-25. Rows marked not yet verified are blank on purpose.

Buying parts

The stock sizes and specs this bike left the factory with, each with its source. Take them to any shop.

Retailer links below are affiliate links: we may earn a commission, at no cost to you, and it never changes the specs. Affiliate disclosure.

Tires
Front tire 80/100-21 Manufacturer spec sheet (research)Rear tire 120/80-19 Manufacturer spec sheet (research)Front tires 80/100-21 at MotoSportTubes 80/100-21 at MotoSportRear tires 120/80-19 at MotoSportTubes 120/80-19 at MotoSport

In stock at MotoSport

Prices from MotoSport’s catalog of Oct 26, 2026; check today’s price before you buy.

Front tire, stock size 80/100-21

Rear tire, stock size 120/80-19

Prices and stock from MotoSport's product catalog on Oct 26, 2026; they change, so check the price at MotoSport before you buy. Products are chosen by exact stock size, code or oil viscosity from the specs above, known brands first, then price. We have not tested them.

9 part specs not yet verified; see data coverage.

Tools for this bike

Compare with

Comparisons with other bikes use the newest model year on file: Yamaha YZ450F 2027.

Other model years

All 7 model years, 2021 to 2027, side by side

Gearing tool

The calculator prefills from this bike once its stock sprockets are verified. It works with any numbers in the meantime.

Open the gearing calculator

What's missing

0 of 31 fields read off a manual page.

Not yet verified (22): front sprocket, rear sprocket, chain pitch, chain links, front rim, rear rim, fork spring rate, shock spring rate, static sag, race sag, engine oil spec, engine oil capacity, coolant capacity, tire pressure (off-road), chain slack, spark plug and gap, fork oil, brake fluid, coolant type, fuel octane, idle speed, valve clearance.

From a spec sheet, awaiting a manual page (9): front tire, rear tire, fork, fork travel, shock travel, fuel capacity, seat height, wheelbase, weight.

See coverage for every bike

Sources

  1. 1
    Yamaha Motor USA 2025 YZ450F specifications pageManufacturer web or spec sheet, research level. Covers front tire, rear tire, fork, fork travel, shock travel, seat height, wheelbase, weight, fuel capacity; checked 2026-09-25.

Always confirm against the manual for your exact year before ordering parts or setting up suspension. Torque specs are deliberately not published here. How we verify a value.

Your manual prints something different? Report a value with the page it is on; every fix is listed in the corrections log.

My settings

Date / track
Sprockets run
Race sag / free sag
Fork air pressure or spring
Fork clickers (compression / rebound)
Shock clickers (low / high / rebound)
Tire pressures (front / rear)
Notes
All bikes