Yuki 125 RS
1978Off-road

Yuki 125 RS

Key specifications

Engine
124 cc
Power
17 HP
Fuel type
petrol
Fuel capacity
3.2 L
Transmission
6-speed
Front brakes
Single disc
Rear brakes
Single disc

Overview

Introducing the 1978 KTM 125 RS, a true gem from the golden era of motocross, perfectly blending performance with the rugged charm of its time. KTM, a name synonymous with off-road excellence, positioned the 125 RS as a formidable contender in the cross-motocross category. This lightweight machine, weighing in at just 111 kg (244.7 lbs) with fluids, was designed for enthusiasts who craved agility and speed on the dirt track. It captured the hearts of riders looking for a nimble yet powerful bike capable of tearing through trails and dominating races. At the heart of the KTM 125 RS lies a spirited single-cylinder, two-stroke engine boasting a displacement of 124 cc. This powerhouse churns out an impressive 17 horsepower at 7,500 RPM, allowing it to reach a top speed of 120 km/h (74.6 mph). The engine's 11.8:1 compression ratio and a bore and stroke of 54 mm by 54 mm ensure a responsive throttle and thrilling acceleration. The air-cooled design contributes to the bike's simplicity and reliability, while the 6-speed gearbox paired with a chain final drive provides seamless gear shifts that enhance the riding experience. Whether navigating tight corners or sprinting down straightaways, the 125 RS delivers an exhilarating ride that leaves competitors in the dust. KTM equipped the 125 RS with features that resonate with performance-oriented riders. The bike showcases a single disc brake system at both the front and rear, offering reliable stopping power when it matters most. This combination of lightweight construction and effective braking contributes to the bike's overall agility, making it an excellent choice for both beginners and seasoned riders. With a fuel capacity of 12 liters (3.17 gallons), riders can enjoy extended adventures without the constant need for refueling, further enhancing its appeal for those long days spent conquering the trails. **

Pros

  • Lightweight and Agile: At just 111 kg, the KTM 125 RS is easy to maneuver, making it ideal for riders who value agility on the track.
  • Strong Performance: The 124 cc two-stroke engine delivers impressive power and acceleration, ensuring a thrilling ride.
  • Durable Construction: Built to endure the rigors of motocross, this bike features robust components that withstand challenging terrains.

Cons

  • Limited Fuel Range: While 12 liters provides decent capacity, it may require more frequent stops during extended rides.
  • Two-Stroke Maintenance: Owners should be prepared for the additional upkeep associated with two-stroke engines, including regular oil mixing and maintenance.
  • Basic Suspension Setup: While effective, the suspension may not offer the advanced adjustability found in modern motocross bikes, potentially limiting customization for some riders.

Technical details

Source specification data

Make
KTM
Model
125 RS
Category
Cross-motocross
Power
17.00 HP (12.4 kW)) @ 7500 RPM
Gearbox
6-speed
Top Speed
120.0 km/h (74.6 mph)
Bore X Stroke
54.0 x 54.0 mm (2.1 x 2.1 inches)
Compression
11.8:1
Displacement
124.00 ccm (7.57 cubic inches)
Cooling System
Air
Engine Details
Single cylinder, two-stroke
Transmission Type Final Drive
Chain
Fuel Capacity
12.00 litres (3.17 gallons)
Weight Incl Oil Gas Etc
111.0 kg (244.7 pounds)
Rear Tyre
3.00-17
Front Tyre
2.75-17
Rear Brakes
Single disc
Front Brakes
Single disc