Yamaha DT 125 MX Specs (Top Speed | Horsepower | Weight)

The Yamaha DT 125 MX motorcycle specifications include a 123 cc (7.51 cu in) engine, power of 14 hp (10.2 kW) @ 7,000 rpm, a 6-speed gearbox, and a listed weight of 102 kg (224.9 lb).

Key specifications

1978Year released
123 ccDisplacement
14 hpPower
9.8 Nm @ 6,500 rpmTorque
102 kgWet weight
845 mmSeat height
7 LFuel tank
265 mmGround clearance

How the Yamaha DT 125 MX 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.

Engine power14 hp
Low 2.8 hpAverage 53.3 hpHigh 171.2 hp

About 74% lower than the Yamaha database average. Around the 24th percentile across Yamaha models.

Displacement123 cc
Low 49 ccAverage 550 ccHigh 1,852 cc

About 78% lower than the Yamaha database average. Around the 13th percentile across Yamaha models.

Wet weight102 kg
Low 72.1 kgAverage 186.3 kgHigh 348.7 kg

About 45% lighter than the Yamaha database average. Around the 12th percentile across Yamaha models.

Seat height845 mm
Low 635 mmAverage 793 mmHigh 989 mm

About 7% taller than the Yamaha database average. Around the 81st percentile across Yamaha models.

Fuel capacity7 L
Low 4 LAverage 13 LHigh 24 L

About 46% smaller than the Yamaha database average. Around the 20th 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.

Engine power24th

14 hp — more powerful than about 24% of Yamaha models with power data.

Displacement13th

123 cc — larger displacement than about 13% of Yamaha models.

Wet weight12th

102 kg — heavier than about 12% of Yamaha models, or lighter than about 88%.

Seat height81st

845 mm — taller than about 81% of Yamaha models.

Fuel capacity20th

7 L — larger than about 20% 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 length2,085 mm
This bike

2,085

Yamaha avg

2,082

Close to average.

Overall width865 mm
This bike

865

Yamaha avg

823

5% above average.

Overall height1,120 mm
This bike

1,120

Yamaha avg

1,172

4% below average.

Seat height845 mm
This bike

845

Yamaha avg

793

7% above average.

Ground clearance265 mm
This bike

265

Yamaha avg

181

47% above average.

Mechanical overview

Engine layout snapshot

Single cylinder, two-stroke • 123 cc • Air cooled • 14 hp
Chassis snapshot

Seat 845 mmClearance 265 mm
6-speed • Chain (final drive) • 2.75-21 front / 3.00-18 rear

Additional useful specifications

Front tire size 2.75-21
Rear tire size 3.00-18
Engine oil capacity 1.00 L (1.06 US qt)
Power-to-weight ratio 0.137 hp/kg
Power-to-weight 137.3 hp/tonne
Specific power 113.8 hp/L
Bore/stroke ratio 1.12:1 (Oversquare)

Model information

Year released 1978
Category Enduro / offroad

Engine specifications

Engine type Single cylinder, two-stroke
Displacement 123 cc (7.51 cu in)
Power 14 hp (10.2 kW) @ 7,000 rpm
Torque 9.8 Nm (1.0 kgf-m or 7.2 ft.lbs) @ 6,500 rpm
Bore × stroke 56.0 x 50 mm (2.2 x 2.0 inches)
Cooling system Air
Fuel system Carburettor. Mikuni VM 24 SH
Fuel control Membrane
Starter Kick
Lubrication Autolube
Oil capacity 1.00 L (1.06 US qt)

Transmission and drivetrain

Gearbox 6-speed
Final drive Chain (final drive)

Chassis and suspension

Front suspension Hydraulic telescopic fork
Rear suspension Monocross
Front wheel travel 180 mm (7.1 inches)
Rear wheel travel 145 mm (5.7 inches)
Rake 30.0°

Brakes, wheels and tires

Front brakes Expanding brake (drum brake)
Rear brakes Expanding brake (drum brake)
Front tire 2.75-21
Rear tire 3.00-18

Dimensions and weight

Wet weight 102 kg (224.9 lb)
Dry weight 95 kg (209.4 lb)
Seat height 845 mm (33.3 inches)
Overall length 2,085 mm (82.1 inches)
Overall width 865 mm (34.1 inches)
Overall height 1,120 mm (44.1 inches)
Ground clearance 265 mm (10.4 inches)

Fuel and emissions

Fuel capacity 7.00 L (1.85 US gal)
Reserve fuel capacity 1.00 L (0.26 US gal)

Performance

Top speed 110.0 km/h (68.4 mph)
Power/weight ratio 0.1474 hp/kg

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.