What category is the 2018 KTM 125 SX?

The 2018 KTM 125 SX has a Category of Cross / motocross.

What is the engine size of the 2018 KTM 125 SX?

The 2018 KTM 125 SX has a Capacity: of 124.80 ccm (7.62 cubic inches).

What type of engine does the 2018 KTM 125 SX have?

The 2018 KTM 125 SX has a Engine type of Single cylinder, two-stroke.

Is the 2018 KTM 125 SX air cooled or liquid cooled?

The 2018 KTM 125 SX has a Cooling system of Liquid.

How many gears does the 2018 KTM 125 SX have?

The 2018 KTM 125 SX has a Gearbox of 6-speed.

How much does the 2018 KTM 125 SX weigh?

The 2018 KTM 125 SX has a Dry weight of 87.2 kg (192.2 pounds).

What is the seat height of the 2018 KTM 125 SX?

The 2018 KTM 125 SX has a Seat height of 960 mm (37.8 inches) If adjustable, lowest setting..

KTM 125 SX - 2018 Specifications and Reviews

The 2018 KTM 125 SX is a lightweight, entry-level motocross bike designed for young riders and beginners entering competitive racing. It combines nimble handling, excellent suspension travel, and aggressive styling in a compact package that rewards technique over brute power. Best known for its reliability and approachable performance, the 125 SX remains the ideal gateway into serious off-road competition.

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2018

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General information
Category	Cross / motocross
Year	2018
Model	KTM 125 SX

Engine and Transmission Specifications
Driveline	13:50. Primary drive: 23:73.
Clutch	Multi-plate clutch, Brembo hydraulics
Transmission type,final drive	Chain
Gearbox	6-speed
Cooling system	Liquid
Ignition	Kokusan EMS
Fuel system	Carburettor. Mikuni TMX
Bore x Stroke	54.0 x 54.5 mm (2.1 x 2.1 inches)
Engine details	Reed intake.
Engine type	Single cylinder, two-stroke
Capacity:	124.80 ccm (7.62 cubic inches)
Brakes, suspension, Frame and wheels
Wheels	CNC machined hubs. Excel rims. Wire spoked.
Rear brakes diameter	220 mm (8.7 inches)
Rear brakes	Single disc. Brake calipers on floating bearings
Front brakes diameter	260 mm (10.2 inches)
Front brakes	Single disc. Brake calipers on floating bearings
Rear wheel travel	300 mm (11.8 inches)
Rear Suspension	WP shock absorber with linkage
Front wheel travel	300 mm (11.8 inches)
Front Suspension	WP-USD, AER 48, Ø 48 mm
Rake (fork angle)	26.5°
Frame type	Chrome-molybdenum steel central-tube frame
Physical measures and capacities
Fuel capacity	7.00 litres (1.85 gallons)
Wheelbase	1,485 mm (58.5 inches)
Ground clearance	375 mm (14.8 inches)
Seat height	960 mm (37.8 inches) If adjustable, lowest setting.
Dry weight	87.2 kg (192.2 pounds)

Other specs
Maintenance	Find parts, fluids, filters, maintenance tools and service items on eBay
Starter	Kick
Color options	Orange/white/black

Performance Profile & Rider Fit

Best For

Track95%

City10%

Cornering90%

Daily Riding10%

Touring8%

Passenger5%

Rider Profile

Best For	This is a full-on motocross competition bike best suited to intermediate through expert off-road riders, not beginners or casual road riders.
Purpose	Built purely for closed-course motocross racing, it excels at jumps, berms, and rapid direction changes on dirt tracks rather than any street use.
Rider Fit	The tall 958 mm seat height, aggressive ergonomics, and demanding 2-stroke power delivery require good rider fitness, strength, and prior dirt bike experience.
Character	Light, explosive, and razor-sharp in handling, it rewards aggressive riding with a peaky two-stroke power band and minimal weight to manage.
Not Ideal For	It is not suitable for commuting, highway travel, passengers, or riders seeking comfort, storage, or a forgiving low-end power delivery.

Character map is an editorial estimate based on this bike's specifications, not a lab-tested measurement.

Rider Fit Visualizer

2018 KTM 125 SX Rider Ergonomics Assessment

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Feet:

At 960mm, a rider of 175cm with a 79cm (estimated) inseam will reach the ground with cannot reach comfortably on the 2018 KTM 125 SX, with a cramped knee angle of around 85 degrees and an upright riding position.

Data quality: measured. Assumes about 30mm of suspension sag once seated (a typical street-bike rule of thumb - stiffer or softer suspension will vary). This is an approximation from category-typical geometry and generic body proportions, not a measurement of this specific bike or you - sit on it before you buy.

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Rider Reviews

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MotorcycleDB Review

The 2018 KTM 125 SX motorcycle is a high-performance, lightweight bike that is perfect for off-road racing and trail riding. With its powerful 125cc engine and top-of-the-line suspension, this motorcycle offers exceptional handling and agility. The bike's sleek design and cutting-edge technology make it a top choice for riders who want a competitive edge on the track. Whether you're a seasoned racer or a beginner, the KTM 125 SX will deliver an adrenaline-pumping ride every time. The 2018 KTM 125 SX motorcycle is a top contender in the 125cc off-road bike category. Its impressive power, precise handling, and advanced features make it a standout choice for riders seeking top performance. Whether you're hitting the trails or competing in races, this bike offers the perfect combination of power and agility. With its sleek design and superior engineering, it's no wonder the KTM 125 SX is a favorite among off-road enthusiasts.