Yamaha RX 125 Specs (Top Speed | Horsepower | Weight)

The Yamaha RX 125 motorcycle specifications include a 125 cc (7.63 cu in) engine, a 5-speed gearbox, and a listed weight of 96 kg (211.6 lb).

Key specifications

1979Year released
125 ccDisplacement
13.3 Nm @ 7,000 rpmTorque
96 kgDry weight
10 LFuel tank
1,240 mmWheelbase
160 mmGround clearance

How the Yamaha RX 125 compares

This compares the motorcycle with all Yamaha models in this specifications database. The blue marker is this model and the grey line is the Yamaha database average.

Displacement125 cc
Low 49 ccAverage 550 ccHigh 1,852 cc

About 77% lower than the Yamaha database average. Around the 25th percentile across Yamaha models.

Fuel capacity10 L
Low 4 LAverage 13 LHigh 24 L

About 23% smaller than the Yamaha database average. Around the 35th percentile across Yamaha models.

This model Yamaha database average

Yamaha database percentile rankings

Percentiles show where this motorcycle sits across the Yamaha specifications database. They are descriptive database rankings, not performance ratings.

Displacement25th

125 cc — larger displacement than about 25% of Yamaha models.

Fuel capacity35th

10 L — larger than about 35% of Yamaha fuel tanks in this database.

Dimensions compared with Yamaha average

Each measurement is compared with the average value across Yamaha models where that dimension is available.

Overall length1,915 mm
This bike

1,915

Yamaha avg

2,082

8% below average.

Overall width730 mm
This bike

730

Yamaha avg

823

11% below average.

Overall height1,060 mm
This bike

1,060

Yamaha avg

1,172

10% below average.

Wheelbase1,240 mm
This bike

1,240

Yamaha avg

1,416

12% below average.

Ground clearance160 mm
This bike

160

Yamaha avg

181

11% below average.

Mechanical overview

Engine layout snapshot

Single cylinder, two-stroke • 125 cc • Air cooled
Chassis snapshot

Wheelbase 1,240 mmClearance 160 mm
5-speed • Chain (final drive) • 3.00-18 front / 3.00-18 rear

Additional useful specifications

Front tire size 3.00-18
Rear tire size 3.00-18
Bore/stroke ratio 1.12:1 (Oversquare)

Model information

Year released 1979

Engine specifications

Engine type Single cylinder, two-stroke
Displacement 125 cc (7.63 cu in)
Torque 13.3 Nm (1.4 kgf-m or 9.8 ft.lbs) @ 7,000 rpm
Bore × stroke 56.0 x 50 mm (2.2 x 2.0 inches)
Compression ratio 6.9:1
Cooling system Air
Fuel system Carburettor. Mikuni VM24SH
Fuel control Port control
Ignition Magneto
Starter Kick
Lubrication Autolube

Transmission and drivetrain

Gearbox 5-speed
Final drive Chain (final drive)

Chassis and suspension

Frame Painted tubular steel
Front suspension Telescopic forks
Rear suspension Swing arm twin shocks

Brakes, wheels and tires

Front brakes Single disc
Rear brakes Expanding brake (drum brake)
Front tire 3.00-18
Rear tire 3.00-18

Dimensions and weight

Dry weight 96 kg (211.6 lb)
Overall length 1,915 mm (75.4 inches)
Overall width 730 mm (28.7 inches)
Overall height 1,060 mm (41.7 inches)
Wheelbase 1,240 mm (48.8 inches)
Ground clearance 160 mm (6.3 inches)

Fuel and emissions

Fuel capacity 10.00 L (2.64 US gal)

Performance

Power/weight ratio 0.1354 hp/kg

Other specifications

Color options Red/black
Exhaust system Single chrome pipe

Disclaimer: Specifications may vary by market, trim, production date and optional equipment, and scraped or historical data can contain errors. Comparison and percentile values are calculated from Yamaha models in this specifications database. Always double-check important specifications against the motorcycle owner’s/service manual and official Yamaha information before relying on them. Visit the official Yamaha website.