Motocross Bikes
2003KTM 50 SX Pro Junior LC
30 fields on record
The 2003 KTM 50 SX Pro Junior LC is a liquid-cooled two-stroke minibike designed for young riders progressing in competitive motocross. Known for its responsive handling and aggressive geometry, this machine excels in youth racing with capable suspension travel and disc braking. The 50cc powerplant delivers spirited performance ideal for developing junior riders' skills on the track.
- Capacity
- 49.8 ccm
- Engine
- Single, two-stroke
- Gearbox
- Not on record
Know it? Add it → - Dry weight
- 37.6 kg
- Seat height
- 585 mm
- Power
- 5.4 HP (4.0 kW)
How it rides
Editorial estimate from the spec sheet - not lab tested- Best for
- It exists purely to teach small kids the basics of motocross racing on a scaled-down, centrifugal-clutch bike that removes the complexity of manual shifting.
- Built for
- Simple, tough, and forgiving in character, with an automatic clutch and mellow two-stroke delivery intended to build confidence rather than deliver thrills.
- Not ideal for
- This bike is not suitable for any adult, teenager, or anyone seeking real speed, comfort, or road-going capability.
Scores are derived from the spec sheet using the same model across every bike, so they compare like for like.
Will it fit you?
Worked out in your browser - nothing is sent to usEngine
- Capacity
- 49.8 ccm
- Power
- 5.4 HP (4.0 kW)
- Engine type
- Single, two-stroke
- Power/weight ratio
- 0.1436 HP/kg (dry)
- Bore x stroke
- 39.5 x 40.0 mm
- Cooling system
- Liquid
- Fuel system
- Carburettor
- Ignition
- Seletra analogue
Transmission
- Transmission type
- Automatic
- Final drive
- Chain
- Clutch
- Centrifugal clutch (adjustable)
Dimensions & weight
- Wheelbase
- 910 mm
- Seat height
- 585 mm
- Dry weight
- 37.6 kg
- Fuel capacity
- 2.00 litres
- Ground clearance
- 220 mm
Chassis & suspension
- Frame
- Central double-cradle-type frame
- Front suspension
- Marzocchi 32 mm
- Rear suspension
- WP monoshock
- Front wheel travel
- 140 mm
- Rear wheel travel
- 205 mm
- Rake (fork angle)
- 24.0°
- Trail
- 69 mm
Brakes & wheels
- Front brakes
- Single disc
- Front brakes diameter
- 160 mm
- Rear brakes
- Expanding brake (drum brake)
- Rear brakes diameter
- 90 mm
- Front tyre
- 2.75-10
- Rear tyre
- 2.50-10
Compiled from manufacturer documentation and user contributions, corrected on an ongoing basis. Spotted something wrong? Tell us.
What changed, year to year
Differences highlighted| Specification | 2003 | 2004 | 2005 |
|---|---|---|---|
| Capacity | 50 cc | 49 cc | 49 cc |
| Dry weight | 38 kg | 38 kg | 38 kg |
| Seat height | 585 mm | 650 mm | 585 mm |
| Fuel capacity | 2 L | 1.8 L | 1.8 L |
Illustrative - generated automatically by diffing the year records already on file, not a manufacturer-published changelog.
Rider Reviews
Common questions
What is the engine size of the KTM 50 SX Pro Junior LC?
The 2003 KTM 50 SX Pro Junior LC has a Capacity of 49.8 ccm (3.04 cubic inches).
What engine power does the KTM 50 SX Pro Junior LC have?
The 2003 KTM 50 SX Pro Junior LC has a Power of 5.4 HP (4.0 kW).
How much does the KTM 50 SX Pro Junior LC weigh?
The 2003 KTM 50 SX Pro Junior LC has a Dry weight of 37.6 kg (82.9 pounds).
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