1987 RM250 Manual

The 1987 Suzuki RM250 is a high-performance motocross motorcycle featuring a 249cc liquid-cooled two-stroke engine, 43mm conventional front forks, full-floating rear suspension system, aluminum swingarm, and competition-focused chassis design. Below are key sections for specifications, maintenance procedures, troubleshooting, and technical data.

1. Specifications 2. Maintenance Schedule 3. Engine Service 4. Chassis & Suspension 5. Electrical System 6. Carburetor Adjustment 7. Troubleshooting 8. Torque Specifications 9. Lubrication Points 10. Safety Precautions

Specifications

Technical specifications for the 1987 Suzuki RM250 motocross motorcycle.

Feature	Specification
Engine Type	249cc liquid-cooled two-stroke single
Bore x Stroke	67.0 x 70.8mm
Compression Ratio	8.4:1
Carburetor	Mikuni VM36SS
Ignition	CDI electronic ignition
Transmission	5-speed constant mesh
Front Suspension	43mm conventional telescopic forks
Rear Suspension	Full-floating system with adjustable preload
Front Brake	Single disc 240mm
Rear Brake	Single disc 240mm
Dry Weight	98 kg (216 lbs)
Fuel Capacity	8.5 liters (2.2 gallons)

Maintenance Schedule

Recommended maintenance intervals for optimal performance.

After each ride: Check tire pressure, chain tension, brake function
Every 10 hours: Clean air filter, check spark plug
Every 20 hours: Change transmission oil, check wheel bearings
Every 40 hours: Replace spark plug, check suspension bearings
Every 80 hours: Top end rebuild, check crank seals

WARNING! Always allow engine to cool before performing maintenance. Use proper safety equipment.

Engine Service

Engine maintenance and repair procedures.

Cylinder and piston: Inspect for scoring, measure ring end gap
Crankcase: Check bearings for smooth rotation, inspect seals
Power valve: Clean and lubricate regularly for optimal performance
Cooling system: Check radiator for leaks, maintain proper coolant level
Exhaust system: Clean expansion chamber, repack silencer

CAUTION! Use genuine Suzuki parts for replacement. Proper torque specifications must be followed.

Chassis & Suspension

Frame: High-tensile steel perimeter design
Front Forks: 43mm conventional with adjustable compression damping
Rear Shock: Gas-charged with adjustable rebound and compression
Swingarm: Aluminum construction with needle bearings
Wheels: Aluminum rims with stainless steel spokes
Tires: Front 80/100-21, Rear 110/90-19
Brakes: Hydraulic disc front and rear

Electrical System

CDI ignition system with lighting coil for competition use.

Components: CDI unit, ignition coil, spark plug (BR8ES), stator assembly, kill switch.

Testing: Check spark plug cap resistance (5k ohms), ignition coil primary resistance (0.1-0.3 ohms), stator output. Battery: Not applicable - magneto powered ignition only.

Carburetor Adjustment

Mikuni VM36SS carburetor settings and jetting specifications.

Main jet: #420 (standard), adjust for altitude and temperature
Pilot jet: #40 (standard)
Needle: 6F21-3 (clip position 3)
Air screw: 1.5 turns out from fully seated
Float height: 16.5mm

Tip: Clean carburetor thoroughly during regular maintenance. Use compressed air for passages.

Troubleshooting

Common issues and solutions for the 1987 RM250.

Symptom	Possible Cause	Corrective Action
Hard starting	Fouled plug, stale fuel	Replace spark plug, drain old fuel, check compression
Poor performance	Clogged air filter, incorrect jetting	Clean air filter, rejet carburetor for conditions
Transmission issues	Worn gears, incorrect oil	Inspect transmission, use proper gear oil
Suspension bottoming	Low oil level, worn springs	Change fork oil, check spring preload
Brake fade	Contaminated fluid, worn pads	Bleed brakes, replace pads and fluid

Torque Specifications

Critical torque values for proper assembly.

Component	Torque Value
Cylinder head nuts	20 Nm (14.5 ft-lbs)
Spark plug	25 Nm (18 ft-lbs)
Front axle nut	65 Nm (47 ft-lbs)
Rear axle nut	100 Nm (72 ft-lbs)
Sprocket bolts	25 Nm (18 ft-lbs)
Engine mount bolts	40 Nm (29 ft-lbs)

Lubrication Points

Regular lubrication maintenance requirements.

Transmission oil: SAE 10W-40, 750ml capacity. Chain: Regular lubrication with chain lube. Bearings: Swingarm, steering head, wheel bearings - grease every 40 hours. Cables: Throttle and clutch cables - lubricate monthly.

WARNING! Use only recommended lubricants. Over-lubrication can attract dirt and cause damage.

Safety Precautions

Always wear proper safety gear including helmet, gloves, boots, and protective clothing. Inspect motorcycle before each ride. Never operate motorcycle on public roads without proper licensing and registration. This is a competition vehicle designed for closed-course use only.