Motocross

Kawasaki KX250

Motocross, 249cc 2T, 2003–2004

Verified

Gearing

5 of 5 filled

Stock front sprocket: 13T; Owner's manual p. 1-11, checked 2026-09-26 (source 1)
Stock rear sprocket: 49T; Owner's manual p. 1-11, checked 2026-09-26 (source 1)
Chain pitch: 520; Owner's manual p. 10-4, checked 2026-09-26 (source 1)
Stock chain links: 114; Owner's manual p. 10-4, checked 2026-09-26 (source 1)
Stock final drive ratio: 3.769 : 1; Owner's manual p. 1-11, checked 2026-09-26 (source 1)

Wheels and tires

4 of 4 filled

Front rim: 21 x 1.60; Owner's manual p. 1-11, checked 2026-09-26 (source 1)
Rear rim: 19 x 2.15; Owner's manual p. 1-11, checked 2026-09-26 (source 1)
Front tire: 80/100-21 51M; Owner's manual p. 1-11, checked 2026-09-26 (source 1)
Rear tire: 110/90-19 62M; Owner's manual p. 1-11, checked 2026-09-26 (source 1)

Suspension

2 of 7 filled

Fork: Not yet verified
Fork travel: 300 mm (11.8 in); Owner's manual p. 1-11, checked 2026-09-26 (source 1)
Shock travel: 310 mm (12.2 in); Owner's manual p. 1-11, checked 2026-09-26 (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

3 of 5 filled

Engine oil spec: Not yet verified
Engine oil capacity: Not yet verified
Coolant capacity: 1200 ml (40.6 fl oz); Owner's manual p. 2-18, checked 2026-09-26 (source 1)
Premix ratio: 32:1; Owner's manual p. 1-10, checked 2026-09-26 (source 1)
Fuel capacity: 8.2 L (2.17 gal); Owner's manual p. 1-10, checked 2026-09-26 (source 1)

Maintenance

3 of 3 filled

Tire pressure (off-road): 100 kPa (1.0 kgf/cm², 14 psi) front and rear; Owner's manual p. 9-4, checked 2026-09-26 (source 1)
Chain slack: 52-62 mm (2.05-2.44 in.); Owner's manual p. 10-4, checked 2026-09-26 (source 1)
Spark plug and gap: NGK BR8EIX; Owner's manual p. 1-10, checked 2026-09-26 (source 1)

Dimensions

2 of 3 filled

Seat height: 945 mm (37.2 in); Owner's manual p. 1-10, checked 2026-09-26 (source 1)
Wheelbase: 1480 mm (58.3 in); Owner's manual p. 1-10, checked 2026-09-26 (source 1)
Weight: 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 2026-09-26. Rows marked not yet verified are blank on purpose.

What's missing

18 of 24 fields read off a manual page.

Not yet verified (6): fork, fork spring rate, shock spring rate, static sag, race sag, weight.

See coverage for every bike

Use this bike

Tools for this bike

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Buying parts

The stock sizes and specs this bike left the factory with, each with its source. Take them to any shop. Retailer links will appear here once a store approves MotoXSports.

Chain: Chain pitch 520 Owner's manual p. 10-4Stock chain links 114 Owner's manual p. 10-4
Sprockets: Stock front sprocket 13T Owner's manual p. 1-11Stock rear sprocket 49T Owner's manual p. 1-11
Tires: Front tire 80/100-21 51M Owner's manual p. 1-11Rear tire 110/90-19 62M Owner's manual p. 1-11
Coolant: Coolant capacity 1200 ml (40.6 fl oz) Owner's manual p. 2-18

4 part specs not yet verified; see data coverage.

Garage tool 01

Sprocket calculator

Put your current gearing in Setup A and the setup you are considering in Setup B. Everything updates as you type.

Start from a bike's stock gearing

Pick a bike to fill both setups with its stock sprockets.

Front sprockets 10–16 teeth, rear 34–60. Values outside that range are brought back to the nearest limit.

Setup A — what you run now

Front teeth

Rear teeth

Setup B — what you are thinking about

Front teeth

Rear teeth

Final drive ratio

— — : 1

—

Pull at the wheel—

Top speed—

Chain (est.)—

A —

B —

Taller · more speed Shorter · more pull

—

Ratios are exact. The chain figure is an estimate of roughly one link per two teeth of change — confirm against your manual before ordering.

Sources

1
Kawasaki KX125/KX250 Motorcycle Service Manual (KX125-M1 to KX125M8F, 2003-2008; KX250-M1 to M2, 2003-2004), Part No. 99924-1298-07, 7th edition; owner-supplied copy, pp. 1-10, 1-11, 2-18, 9-4, 10-4Manual page, verified. Covers stock front sprocket, stock rear sprocket, chain pitch, stock chain links, stock final drive ratio, front rim, rear rim, front tire, rear tire, fork travel, shock travel, coolant capacity, fuel capacity, premix ratio, tire pressure (off-road), chain slack, spark plug and gap, seat height, wheelbase; checked 2026-09-26.

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

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

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