1988 Yamaha DT50 Manual

The 1988 Yamaha DT50 is a lightweight dual-sport motorcycle featuring a 49cc air-cooled two-stroke engine, 5-speed transmission, front and rear drum brakes, and dual-purpose tires. Designed for both on-road and off-road use, this versatile motorcycle offers excellent fuel economy and maneuverability. Below are key sections covering specifications, operation, maintenance, troubleshooting, and safety information.

1. Specifications 2. Controls and Instruments 3. Operation Instructions 4. Maintenance Schedule 5. Fuel and Lubrication 6. Electrical System 7. Brake System 8. Tire Information 9. Storage Guidelines 10. Troubleshooting 11. Safety Precautions

Specifications

Detailed technical specifications for the 1988 Yamaha DT50 motorcycle.

Component	Specification
Engine Type	Air-cooled, 2-stroke single cylinder
Displacement	49cc
Bore x Stroke	40.0mm x 39.2mm
Compression Ratio	6.5:1
Carburetor	VM16SC
Transmission	5-speed constant mesh
Final Drive	Chain
Front Suspension	Telescopic fork
Rear Suspension	Swingarm with dual shocks
Front Brake	Drum, 110mm
Rear Brake	Drum, 110mm
Fuel Capacity	7.5 liters (2.0 gallons)
Dry Weight	82 kg (181 lbs)

Controls and Instruments

Overview of motorcycle controls and instrument panel functions.

Control	Function
Right Handlebar	Front brake lever, throttle grip
Left Handlebar	Clutch lever, light switch, horn button
Instrument Panel	Speedometer, odometer, neutral indicator
Foot Controls	Gear shift lever, rear brake pedal
Kick Starter	Engine starting mechanism
Fuel Tap	ON/OFF/RESERVE positions
Choke Lever	Cold start enrichment

Operation Instructions

Proper starting, riding, and shutting down procedures.

Pre-ride inspection: Check fuel, oil, tires, brakes, and controls
Starting procedure: Turn fuel tap to ON, set choke for cold starts, kick start
Warm-up: Allow engine to warm for 2-3 minutes before riding
Shifting: Use clutch smoothly, shift through 5 gears as needed
Braking: Apply both brakes progressively for safe stopping
Shutdown: Turn fuel tap to OFF after riding

WARNING! Always wear proper protective gear including helmet, gloves, and boots.

Maintenance Schedule

Recommended maintenance intervals for optimal performance.

Service Item	Every 1,000 km	Every 3,000 km	Every 6,000 km
Spark Plug	Inspect/Clean	Replace	-
Air Filter	Clean	Replace	-
Engine Oil	Change	-	-
Chain Adjustment	Check/Adjust	-	-
Brake Adjustment	Check	Inspect pads	Replace if worn
Tire Pressure	Check weekly	-	-

Fuel and Lubrication

Fuel mixture requirements and lubrication points.

Fuel Mixture: 50:1 ratio (2% oil) with premium unleaded gasoline
Recommended Oil: Yamaha 2-stroke oil or equivalent
Engine Oil Capacity: 650ml at change
Transmission Oil: SAE 10W-30, 650ml capacity
Chain Lubrication: Apply chain lube every 500 km
Cable Lubrication: Lubricate control cables every 3,000 km

CAUTION! Always mix fuel thoroughly before refueling.

Electrical System

Electrical components and maintenance procedures.

Component	Specification	Maintenance
Battery	6V 4Ah	Check electrolyte monthly
Spark Plug	BR8HS	Gap: 0.6-0.7mm
Headlight	6V 25/25W	Check alignment periodically
Tail Light	6V 5/18W	Replace if dim or broken
Fuse	10A	Carry spare fuse

Brake System

Brake maintenance and adjustment procedures.

Front brake adjustment: Turn adjuster on handlebar lever
Rear brake adjustment: Turn adjuster on brake rod
Brake shoe inspection: Check for wear every 3,000 km
Drum cleaning: Clean brake drums when replacing shoes
Cable lubrication: Lubricate brake cables every 6 months

WARNING! Worn brake shoes significantly reduce stopping power.

Tire Information

Tire specifications and maintenance guidelines.

Front Tire: 2.50-18, 28 psi (1.9 bar)
Rear Tire: 2.75-18, 32 psi (2.2 bar)
Tire Type: Dual-purpose knobby
Tread Depth: Replace when below 1.5mm
Inspection: Check for damage and wear weekly
Rotation: Not applicable due to different tire sizes

Storage Guidelines

Proper storage procedures for extended periods.

Fuel system: Add fuel stabilizer and run engine for 5 minutes
Battery: Remove and store fully charged in cool, dry place
Tires: Inflate to recommended pressure and elevate off ground
Exterior: Clean thoroughly and apply protective wax
Cover: Use breathable motorcycle cover
Restarting: Drain old fuel, check all systems before riding

Troubleshooting

Common problems and their solutions.

Symptom	Possible Cause	Corrective Action
Engine won't start	No spark, fuel issue, compression	Check spark plug, fuel flow, compression
Poor performance	Clogged air filter, carb issues	Clean air filter, check carburetor
Hard shifting	Low oil, clutch adjustment	Check oil level, adjust clutch cable
Weak brakes	Worn shoes, cable stretch	Replace shoes, adjust cables
Electrical failure	Blown fuse, bad connection	Check fuse, clean connections
Chain noise	Loose chain, lack of lubrication	Adjust tension, lubricate chain

Safety Precautions

Essential safety information for riders.

Always wear DOT-approved helmet
Use protective clothing: jacket, gloves, boots
Perform pre-ride inspection before every ride
Observe all traffic laws and speed limits
Never operate under influence of alcohol/drugs
Take motorcycle safety course for beginners
Be visible: Use lights and reflective gear
Maintain safe following distance

EMERGENCY CONTACT: Yamaha Customer Service: 1-800-962-7926