Target Audience:
Owners of Yamaha TTR90 motorcycles seeking to perform their own maintenance and repairs, as well as independent repair shops and enthusiasts.
Value Proposition:
Provides detailed, authoritative information essential for maintaining the TTR90's performance and longevity, offering cost savings over dealership service.
Manual Comprehensiveness:
Covers all aspects of the motorcycle, from basic servicing to complex overhauls.
Diagrams And Illustrations:
Includes detailed exploded views, schematics, and troubleshooting flowcharts to aid understanding.
Engine Overhaul:
Complete disassembly, inspection, repair, and reassembly of engine components (cylinder, piston, crankshaft, valvetrain, carburetor, ignition).
Transmission Service:
Inspection, repair, and adjustment of the gearbox, clutch, and shift mechanisms.
Chassis And Suspension:
Front fork (including oil changes and seal replacement), rear shock absorber, swingarm, bearings, and frame inspection.
Braking System:
Front and rear brake caliper service, brake pad replacement, brake fluid bleeding, brake line inspection.
Electrical System:
Wiring diagrams, ignition system troubleshooting (CDI, spark plug), lighting system, charging system (stator, regulator/rectifier), battery maintenance.
Fuel System:
Carburetor cleaning, adjustment, and jetting; fuel tank and petcock inspection; fuel filter replacement.
Cooling System:
N/A (The TTR90 is air-cooled)
Routine Maintenance:
Oil changes, filter replacements, chain adjustment, spark plug checks, valve clearance checks.
Troubleshooting Guides:
Systematic diagnostic procedures for common performance issues, starting problems, and electrical faults.
Component Replacement:
Detailed instructions for replacing major and minor components.
Specifications And Tolerances:
Torque specifications for all fasteners, piston ring gap, valve clearance, ignition timing, and other critical measurements.
Diagnostic Capabilities:
Advanced diagnostic procedures for identifying root causes of malfunctions, including electrical testing and mechanical checks.
Rebuild Procedures:
Comprehensive step-by-step guides for complete engine and transmission rebuilds.
Engine Type:
4-stroke, SOHC, 2-valve
Bore X Stroke:
49 mm x 47 mm
Cooling System:
Air-cooled
Carburetion:
Teikei Y24P (or similar Mikuni VM series) 24mm slide valve carburetor
Horsepower Estimated:
Approx. 8-9 HP (at crankshaft, specific figures may vary by region and tuning)
Torque Estimated:
Approx. 7-8 Nm (at crankshaft, specific figures may vary)
Fuel Type:
Unleaded gasoline
Fuel Tank Capacity:
3.6 Liters (0.95 US gal)
Ignition System:
CDI (Capacitor Discharge Ignition)
Engine Oil Change:
Every 1000 km or 6 months (refer to manual for specific Yamaha recommendations).
Spark Plug Inspection:
Every 2000 km or 12 months.
Valve Clearance Check:
Every 6000 km or 36 months.
Air Filter Cleaning:
Regularly, especially in dusty conditions (recommendation: monthly or as needed).
Chain Lubrication And Adjustment:
Every 500 km or as needed based on slack.
Engine Oil Type:
Yamalube 4 (or equivalent) SAE 10W-30 API SE type SF or SG (check manual for exact specification).
Engine Oil Capacity:
0.90 Liters (0.95 US qt) without filter change; 1.00 Liter (1.05 US qt) with filter change.
Brake Fluid Type:
DOT 3 or DOT 4 (check manual for specific recommendation).
Carburetor Clogging:
Common in small displacement engines, particularly with fuel sitting for extended periods. Regular cleaning and proper fuel storage are key.
Chain And Sprockets Wear:
Typical wear item for dirt bikes; requires regular adjustment, lubrication, and eventual replacement.
Suspension Seal Leaks:
Front fork seals can wear over time, leading to oil leaks. Service and replacement are detailed in the manual.
Yamaha Motorcycle Legacy:
Yamaha has a long-standing reputation for producing reliable and performance-oriented motorcycles across various disciplines, including motocross and trail riding.
Ttr Series Introduction:
The TTR series was introduced to offer accessible and user-friendly off-road motorcycles for younger riders and beginners, bridging the gap between mini-bikes and full-sized dirt bikes.
Production Period:
The TTR90 was primarily produced in the early 2000s, with this 2002 model being a key year in its production run. Variations and updates may exist for other model years.
Industry Awards:
While specific awards for the TTR90 model might be scarce, Yamaha's TTR line generally received positive reviews for its accessibility and reliability in the entry-level off-road segment.
Consumer Satisfaction:
Owners generally praise the TTR90 for its ease of use, low maintenance requirements, and durability for its class.
Safety Certifications:
N/A (as it's an off-road vehicle).
