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KTM 50 SX 2017
NEVER TOO YOUNG TO LEARN

 
  The 50 SX is a true KTM for young MX riders aged from around 4 to 10 years old and up to a body height of 1.30m. It is a genuine dirt bike that, like its bigger siblings, is produced with top-quality components. This makes the 50 SX the first choice as a stepping stone into the world of MX or for the first racing step on the ladder. With the youngster in mind this package has an engine that delivers steady, controllable power, incorporating an automatic clutch that is ideal for novice riders. This year’s model features revolutionary WP AER 35 front forks, fully adjustable rear suspension, a new exhaust, ultra cool graphics and a lot of detail improvements that make going fast, fun. And safe.  
     
   
     
 

CUTTING-EDGE 2-STROKE TECHNOLOGY

 
                         
                   
   

ENGINE

     

CLUTCH

     

EXHAUST

   
    The modern, extremely compact 2-stroke engine fitted with an automatic clutch sets the standard in its class with improved power and power band due to a new exhaust pipe. Thanks to the 3-shaft design, the crankshaft is close to the bike’s center of gravity. This does not just benefit the handling, but also allows for a flow optimized intake angle into the reed valve – a prerequisite for maximum performance.       Developed by KTM, the centrifugal multi-disc automatic clutch provides manageable acceleration and makes riding this motorcycle the easiest thing in the world. It can be adjusted to the specific requirements of the track and the rider in minutes and without any special tools.       A newly developed exhaust pipe provides a higher output and a smoother power delivery over the entire rev range, making the new 50 SX even more competitive than before.    
                         
     
 

POWER REDUCTION KIT

 
  For absolute beginners the engine power can be reduced to a moderate 5.5hp using a kit from the PowerParts program.  
     
     
 

CYLINDER

 
  The high performance cylinder features a pressure controlled exhaust valve (PCEV) and provides an unrivaled performance within the highly competitive 50cm3 class.  
     
     
 

IMPROVED ERGONOMICS

 
                         
                   
   

RADIATOR

     

FRAME

     

GRAPHICS

   
    Like the big KTM bikes, the 50 SX has a liquid cooling system, which even cools the crankcase. Generously sized radiators ensure outstanding heat dissipation for high reliability, even under extremely heavy duty.       The modern frame produced by WP Performance Systems is made of lightweight, high strength chromoly steel profiles and combines maximum longitudinal stiffness with optimum torsional rigidity. It guarantees easy handling and precise cornering, but also outstanding stability.       Derived from the full-size SX bikes, the graphic design makes the new 50 SX look even cooler. Its frame has a super rugged polymer coating in cheeky black.    
                         
                         
                         
                     
   

BODYWORK

      HANDLEBARS            
    The bodywork is derived from the full-size SX models and provides perfect ergonomics, well thought-out contact points for the rider and maximum freedom of movement. In addition, smart design solutions for the new front and rear fenders are prime examples of an intelligent design, which guarantees maximum stability through a well thought-out structure and mounting.       Made of high quality aluminum alloy, the handlebars offer top stability and safety. A crash pad on the handlebar brace protects our dearest from rough contact.            
                         
                         
 

CHASSIS

 
                         
                   
   

SWINGARM

     

FRONT SUSPENSION

     

REAR SUSPENSION

   
    The 50 SX is fitted with a lightweight cast aluminum swingarm. Conceived using the latest in calculation and simulation software, the design and wall thickness have been made for minimum weight at optimum stiffness and precisely defined flexibility. In addition it features a robust 2-compound chain guide similar to the full-size models.       The new 50 SX is the first model in its class fitted with a modern, fully adjustable air fork: the AER 35, made by WP Suspension. Beside a massive weight reduction of 750g the newly developed upside-down front forks with 35mm tube diameter and 205mm of travel ensure outstanding comfort, damping characteristics and directional stability. Another main benefit for junior riders is that the air spring fitted in the left fork leg can be adjusted perfectly to the rider’s weight just with a simple air fork pump.       On the rear wheel a WP monoshock linked directly to the swingarm provides excellent damping performance and is now fully adjustable in order set the damping perfectly to rider’s preferences and track conditions. The rear wheel travel is 185mm.    
                         
                         
                         
                     
   

WHEELS

     

BRAKES

           
    Like the big KTM factory racers, the 50 SX has super lightweight, black anodized, aluminum rims providing highest strength and safety. The OEM knobbly MAXXIS tires grip superbly on any surface.       The 50 SX is fitted with front and rear hydraulic brakes by Formula combined with lightweight wave discs that are easy to control even for the youngest riders. This ensures the best deceleration and the highest standard when it comes to safety.            
                         
                         
 
 
     
 

ENGINE

 
 
  • Design

    1-cylinder, 2-stroke engine


  • Displacement

    49 cm³


  • Bore

    39.5 mm


 
  • Stroke

    40 mm


  • Starter

    Kickstarter


  • Transmission

    Single-speed automatic


 
  • Primary drive

    61:33


  • Secondary gear ratio

    11:40


  • Clutch

    Centrifugal clutch (adjustable)


  • EMS

    Seletra 2p D36


 
             
 

SHASSIS

 
 
  • Frame design

    Central-tube frame with double-cradle


  • Front suspension

    WP-USD, AER 35, Ø 35 mm


  • Rear suspension

    WP shock absorber


  • Suspension travel (front)

    205 mm


  • Suspension travel (rear)

    185 mm


 
  • Front brake

    Disc brake


  • Rear brake

    Disc brake


  • Front brake disc diameter

    160 mm


  • Rear brake disc diameter

    160 mm


  • Chain

    1/2 x 3/16"


 
  • Steering head angle

    66 °


  • Wheelbase

    1032 ± 10 mm


  • Ground clearance

    252 mm


  • Seat height

    684 mm


  • Tank capacity (approx.)

    2.3 l


  • Weight READY TO RACE (without fuel)

    41.5 kg