The Garage

Motocross

Stock-size parts in stock at MotoSport

Triumph TF 250-X 2026

Motocross, 250cc 4T, US version

Partly verified

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

Model year on file: 2026 only. Other years are added as their manuals are read.

No CPSC recall found for the 2026 Triumph TF 250-X, checked 2026-10-15. Recalls

Spec card PDF

Gearing

3 of 5 filled

Stock front sprocket
13T
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Stock rear sprocket
48T
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Chain pitch
Not yet verified
Stock chain links
Not yet verified
Stock final drive ratio
3.69 : 1
Calculated, not printed: Calculated from the stock sprockets (research-level inputs)

Wheels and tires

4 of 4 filled

Front rim
21 x 1.6
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Rear rim
19 x 1.85
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Front tire
80/100-21
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Rear tire
100/90-19
Research level: Spec sheet (research) · checked 2026-09-27 source [1]

Suspension

3 of 7 filled

Fork
KYB 48mm coil spring fork
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Fork travel
310 mm (≈ 12.2 in, converted by MotoXSports)
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Shock travel
305 mm (≈ 12.0 in, converted by MotoXSports)
Research level: Spec sheet (research) · checked 2026-09-27 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
7 L (≈ 1.85 gal, converted by MotoXSports)
Research level: Spec sheet (research) · checked 2026-10-16 source [1]

Dimensions

3 of 3 filled

Seat height
960 mm (≈ 37.8 in, converted by MotoXSports)
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Wheelbase
1492 mm (≈ 58.7 in, converted by MotoXSports)
Research level: Spec sheet (research) · checked 2026-09-27 source [1]
Weight
229.3 lb (≈ 104 kg, converted by MotoXSports)
Research level: Spec sheet (research) · converted from 229.3 lb · checked 2026-09-27 source [1]

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 2026-10-16. 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.

Sprockets
Stock front sprocket 13T Manufacturer spec sheet (research)Stock rear sprocket 48T Manufacturer spec sheet (research)13T front sprockets at MotoSport48T rear sprockets at MotoSport
Tires
Front tire 80/100-21 Manufacturer spec sheet (research)Rear tire 100/90-19 Manufacturer spec sheet (research)Front tires 80/100-21 at MotoSportTubes 80/100-21 at MotoSportRear tires 100/90-19 at MotoSportTubes 100/90-19 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 100/90-19

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.

7 part specs not yet verified; see data coverage.

Tools for this bike

Compare with

All 27 comparisons for this bike

Gearing calculator

Gearing for this bike

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

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

Front sprockets 8–16 teeth, rear 34–60. Values outside that range are brought back to the nearest limit.

Setup A — what you run now
Setup B — what you are thinking about
Final drive ratio

— — : 1

—
Pull at the wheel—
Top speed—
Ratio change—
A —
B —
Taller · more speed Shorter · more pull

—

Changing the rear sprocket changes the chain length too. The chain length calculator works it out from the chain you have now, with where the axle ends up.

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

What's missing

0 of 31 fields read off a manual page.

Not yet verified (18): chain pitch, chain links, 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 (13): front sprocket, rear sprocket, front rim, rear rim, front tire, rear tire, fork, fork travel, shock travel, fuel capacity, seat height, wheelbase, weight.

See coverage for every bike

Sources

  1. 1
    Triumph 2026 TF 250-X specifications (triumphmotorcycles.com, US)Manufacturer web or spec sheet, research level. Covers stock front sprocket, stock rear sprocket, front rim, rear rim, front tire, rear tire, fork, fork travel, shock travel, fuel capacity, seat height, wheelbase, weight; checked 2026-10-16.

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
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