The Garage

Enduro

Stock-size parts in stock at MotoSport

GasGas EX 300 2027

Enduro, 293.15cc 2T, US version

Verified

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

From the owner’s manual: premix 60:1, p. 132; coolant 0.95 l, p. 130; front tire 80/100-21 51M TT, p. 132; rear tire 110/100-18 64M TT, p. 132. Checked 16 Oct 2026.

Model year on file: 2027 only. Other years are added as their manuals are read.

No CPSC recall found for the 2027 GasGas EX 300, checked 2026-10-15. Recalls

GasGas EX 300 2027

Workshop card from motoxsports.com/bikes/gasgas-ex-300/ · each figure as the maker’s document prints it, with its source number; ≈ marks a figure we converted. Torque values are not published: use the manual.

Gearing

4 of 5 filled

Stock front sprocket
14T
Verified, read off the manual page: Manual p. 131 · checked 2026-10-11 source [1]
Stock rear sprocket
48T
Verified, read off the manual page: Manual p. 131 · checked 2026-10-11 source [1]
Chain pitch
520
Calculated, not printed: The trade name of the printed size 5/8 x 1/4" · Manual p. 131 · checked 2026-10-11 source [1]
Stock chain links
Not yet verified
Stock final drive ratio
3.43 : 1
Calculated, not printed: Calculated from the stock sprockets, printed on manual p. 131

Wheels and tires

4 of 4 filled

Front rim
1.60 x 21"
Research level: Spec sheet (research) · checked 2026-10-11 source [2]
Rear rim
2.15 x 18"
Research level: Spec sheet (research) · checked 2026-10-11 source [2]
Front tire
80/100-21 51M TT
Verified, read off the manual page: Manual p. 132 · checked 2026-10-11 source [1]
Rear tire
110/100-18 64M TT
Verified, read off the manual page: Manual p. 132 · checked 2026-10-11 source [1]

Suspension

3 of 7 filled

Fork
WP XPLOR CC
Verified, read off the manual page: Manual p. 132 · checked 2026-10-11 source [1]
Fork travel
300 mm (11.81 in)
Verified, read off the manual page: Manual p. 131 · checked 2026-10-11 source [1]
Shock travel
300 mm (11.81 in)
Verified, read off the manual page: Manual p. 131 · checked 2026-10-11 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 3 filled

Coolant capacity
0.95 l (≈ 32.1 fl oz, converted by MotoXSports)
Verified, read off the manual page: Manual p. 130 · checked 2026-10-11 source [1]
Premix ratio
60:1
Verified, read off the manual page: Manual p. 132 · checked 2026-10-11 source [1]
Fuel capacity
9 l (≈ 2.38 gal, converted by MotoXSports)
Verified, read off the manual page: Manual p. 132 · checked 2026-10-11 source [1]

Service specs

6 of 6 filled

Gearbox oil
0.8 l (0.21 liq. galUS); Engine oil (15W/50), Partially synthetic
Verified, read off the manual page: Manual p. 130 · checked 2026-10-16 source [1]
Fork oil
Fork oil (SAE 4): outer assembly 390 ml (13.19 fl. ozUS); cartridge 175 ml (5.92 fl. ozUS)
Verified, read off the manual page: Manual p. 133 · checked 2026-10-16 source [1]
Brake fluid
DOT 5.1
Verified, read off the manual page: Manual p. 143 · checked 2026-10-16 source [1]
Coolant type
COOLANT M3.0, recommended supplier MOTOREX®; antifreeze protection to at least −25 °C (−13.0 °F)
Verified, read off the manual page: Manual p. 143 · checked 2026-10-16 source [1]
Fuel octane
Super unleaded (95 octane)
Verified, read off the manual page: Manual p. 144 · checked 2026-10-16 source [1]
Idle speed
1,500 rpm … 1,700 rpm (25.00 Hz … 28.33 Hz)
Verified, read off the manual page: Manual p. 130 · checked 2026-10-16 source [1]

Maintenance

3 of 3 filled

Tire pressure (off-road)
1.0 bar (14.5 psi) front; 1.0 bar (14.5 psi) rear
Verified, read off the manual page: Manual p. 131 · checked 2026-10-11 source [1]
Chain slack
55 mm … 58 mm (2.17 in … 2.28 in)
Verified, read off the manual page: Manual p. 69 · checked 2026-10-11 source [1]
Spark plug and gap
NGK BR 8 ES
Verified, read off the manual page: Manual p. 130 · checked 2026-10-11 source [1]

Dimensions

3 of 3 filled

Seat height
957 mm (37.68 in)
Verified, read off the manual page: Manual p. 131 · checked 2026-10-11 source [1]
Wheelbase
1489 mm (≈ 58.6 in, converted by MotoXSports)
Verified, read off the manual page: Manual p. 131 · checked 2026-10-11 source [1]
Weight (weight without fuel approx.)
102.5 kg (225.97 lb)
Verified, read off the manual page: Manual p. 131 · checked 2026-10-11 source [1]
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.

Chain
Chain pitch 520 Owner's manual p. 131520 chains at MotoSport520 master links at MotoSport
Sprockets
Stock front sprocket 14T Owner's manual p. 131Stock rear sprocket 48T Owner's manual p. 13114T front sprockets at MotoSport48T rear sprockets at MotoSport
Tires
Front tire 80/100-21 51M TT Owner's manual p. 132Rear tire 110/100-18 64M TT Owner's manual p. 132Front tires 80/100-21 at MotoSportTubes 80/100-21 at MotoSportRear tires 110/100-18 at MotoSportTubes 110/100-18 at MotoSport
Coolant
Coolant capacity 950 ml (32.1 fl oz) Owner's manual p. 130Coolant at MotoSport

In stock at MotoSport

Prices from MotoSport’s catalog of Oct 14, 2026; check today’s price before you buy.

Front tire, stock size 80/100-21

Rear tire, stock size 110/100-18

Spark plug, stock NGK BR 8 ES

Prices and stock from MotoSport's product catalog on Oct 14, 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.

3 part specs not yet verified; see data coverage.

Tools for this bike

Compare with

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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

23 of 30 fields read off a manual page.

Not yet verified (5): chain links, fork spring rate, shock spring rate, static sag, race sag.

From a spec sheet, awaiting a manual page (2): front rim, rear rim.

See coverage for every bike

Sources

  1. 1
    GASGAS Owner's manual 2027, EX 300, item no. 3215289en, dated 31/08/2026 (KTM Group print-on-demand portal, file 27_3215289_en_BA.pdf, read from the portal's page preview)pp. 69, 130, 131, 132, 133, 143, 144Manual page, verified. Covers stock front sprocket, stock rear sprocket, chain pitch, front tire, rear tire, fork, fork travel, shock travel, coolant capacity, fuel capacity, premix ratio, tire pressure (off-road), spark plug and gap, chain slack, seat height, wheelbase, weight (weight without fuel approx.), weight, as labelled, gearbox oil, fork oil, brake fluid, coolant type, fuel octane, idle speed; checked 2026-10-16.
  2. 2
    EX 300 2027 | GASGAS United States (model page, Technical Details 'SHOW ALL' panel)Manufacturer web or spec sheet, research level. Covers front rim, rear rim; checked 2026-10-11.

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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