🏷️ Basic Information

Make:

Yamaha

Model:

YZ85

Model Variant:

Motocross Motorcycle

Product Name:

Yamaha YZ 85 2007-2012 Motocross Motorcycle Service Repair Workshop Manual

Covered Years:

2007, 2008, 2009, 2010, 2011, 2012

Chassis Code Range:

Likely variations of 5BM, 4SP, 14B, 14C for this generation. Specific codes would be detailed within the manual.

👋 Introduction

Category:

Entry-level to intermediate motocross competition, youth racing.

Target Audience:

Motocross racers, mechanics, and dedicated hobbyists maintaining and repairing Yamaha YZ85 models.

Competitors:

KTM 85 SX, Kawasaki KX85, Suzuki RM85, Honda CRF150R (though the CRF150R is a 4-stroke, it competes in a similar displacement class).

Engine Type:

Liquid-cooled, 2-stroke, single-cylinder.

Suspension Front:

Upside-down telescopic forks with adjustable compression and rebound damping.

Suspension Rear:

Monocross rear suspension with adjustable preload, compression, and rebound damping.

Value Proposition:

Provides essential technical knowledge for maintaining optimal performance and ensuring longevity of the YZ85.

📋 Manual Details

Primary Coverage:

Comprehensive service, repair, and maintenance for Yamaha YZ85 motocross motorcycles

Specific Years Covered:

2007, 2008, 2009, 2010, 2011, 2012

Estimated Page Count:

Likely between 300-500 pages, typical for a complete service manual. Exact count not provided in product info.

Type:

Service Repair Workshop Manual

Language:

English

Format:

Digital (likely PDF, common for online sales). Physical print versions may also be available.

📖 Manual Coverage

Engine:

Top-end (cylinder, piston, rings, head), bottom-end (crankshaft, connecting rod, bearings), lubrication system, cooling system (if applicable to the specific model year's design), fuel and exhaust systems.

Transmission:

Clutch assembly, gearbox (gears, shift drum, shift forks), final drive (sprockets, chain).

Chassis:

Frame, front suspension (forks, triple clamps), rear suspension (shock absorber, linkage, swingarm), steering system, wheels, tires, braking system (front and rear), footpegs, seat.

Electrical:

Ignition system, lighting (if equipped), wiring diagrams, switches, fuses, battery (if applicable), coil, CDI unit.

Fuel System:

Carburetor (disassembly, cleaning, adjustment), fuel lines, fuel petcock.

Maintenance:

Routine checks, oil changes, filter cleaning/replacement, chain adjustment, brake pad inspection, spark plug service, air filter cleaning.

Troubleshooting:

Diagnostic charts for common problems, symptom-based problem resolution, electrical system diagnosis.

Repair:

Engine disassembly and reassembly, transmission overhauls, suspension servicing, brake system repairs, carburetor rebuilding, clutch replacement, wheel bearing replacement.

Installation:

Instructions for installing aftermarket or replacement parts (e.g., exhaust systems, seat covers, graphics kits), often referencing correct torque values and procedures.

Depth:

Comprehensive. Covers basic maintenance to complete engine and chassis rebuilds. Includes detailed exploded views, torque specifications, and diagnostic information.

📊 Manual Specifications

Digital Format:

Likely PDF. Searchable text capability is a significant advantage for digital formats.

Print Quality Digital:

High resolution for clear text and diagrams. Designed for digital viewing and printing of specific sections.

Binding Type Physical:

If a physical copy, typically spiral-bound or perfect-bound for lay-flat use in a workshop environment.

Paper Type Physical:

Heavy-duty, glossy or semi-gloss paper to withstand workshop conditions and provide durability for diagrams and photos.

⚙️ Engine Specifications

Engine Type:

Liquid-cooled, 2-stroke, reed valve, single-cylinder

Displacement:

84.7 cc

Bore X Stroke:

47.5 mm x 47.1 mm

Compression Ratio:

Likely around 8.2:1 to 8.6:1 depending on exact year and market. Manual will specify.

Cylinder Material:

Aluminum with steel cylinder liner

Horsepower Estimate:

Typically in the range of 21-23 HP at the crank. Manual will provide precise figures.

Torque Estimate:

Estimated around 9-10 lb-ft. Manual will provide precise figures.

Carburetor Type:

Mikuni VM28SS (or similar Mikuni model).

Carburetor Features:

Flat-slide, constant velocity (CV) or non-CV type depending on specific year. Manual details jetting, needle settings, float height.

Mixture Ratio:

Typically 50:1 or 40:1 with pre-mix gasoline. Manual will specify the exact recommended ratio and Yamalube type.

Ignition System:

CDI (Capacitor Discharge Ignition)

Cooling Method:

Liquid-cooled

Starter System:

Kickstarter

🔧 Transmission

Transmission Type:

6-speed constant mesh

Clutch Type:

Wet, multiple-disc

Final Drive:

Chain drive

Gear Ratios:

Specific gear ratios for each of the 6 speeds will be detailed in the manual.

Clutch Lever Adjustment:

Service manual will provide instructions for adjusting clutch free play.

📐 Dimensions

Length:

Approximately 1840 mm (72.4 in) for this generation. Manual will confirm.

Width:

Approximately 760 mm (29.9 in) for this generation. Manual will confirm.

Height:

Approximately 1150 mm (45.3 in) for this generation. Manual will confirm.

Seat Height:

Approximately 880 mm (34.6 in) for this generation. Manual will confirm.

Wheelbase:

Approximately 1240 mm (48.8 in) for this generation. Manual will confirm.

Dry Weight:

Approximately 73 kg (161 lbs) for this generation. Manual will confirm.

Fuel Tank Capacity:

Approximately 5.0 Liters (1.3 US gal). Manual will confirm.

Oil Capacity Transmission:

Approximately 0.75 Liters (0.79 US qt) of Yamalube Gear Oil 10W-40 or equivalent. Manual will specify exact capacity and fluid type.

🛡️ Safety Features

Safety Ratings:

Not applicable in the same way as street vehicles. Focus is on rider protection and machine integrity.

Braking System Front:

Hydraulic disc brake, single caliper.

Braking System Rear:

Hydraulic disc brake, single caliper.

Frame Construction:

Semi-double cradle frame, designed for strength and rigidity.

Handguards:

Often fitted as standard or a common aftermarket addition for hand protection. Manual may cover installation.

💡 Technology Features

Infotainment System:

Not applicable. This is a pure motocross competition machine, devoid of electronic comfort or infotainment features.

Driver Assistance Features:

None. Focus is on rider skill and machine control.

Connectivity Features:

None. Designed for off-road racing.

Power Valve:

Features Yamaha's YPVS (Yamaha Power Valve System) for optimized power delivery across the RPM range. Manual details its function, cleaning, and adjustment.

🔧 Maintenance

Oil Change Transmission:

Every 10-15 hours of riding or annually. Manual will specify recommended interval based on usage.

Air Filter Cleaning:

After every few rides, or more frequently in dusty conditions. Manual details cleaning and oiling procedure.

Spark Plug Service:

Inspect every 10-15 hours, replace as needed. Manual provides correct plug type and gap.

Chain Tension Adjustment:

Check and adjust before every ride or as needed based on slack.

Transmission Oil:

Yamalube Gear Oil 10W-40 or SAE 80 hypoid gear oil (API GL-4). Manual will confirm precise specification.

Coolant Type:

Yamaha's recommended coolant (e.g., Yamalube Coolant) or a 50/50 mix of ethylene glycol and distilled water. Manual will specify.

Brake Fluid:

DOT 4 hydraulic brake fluid. Manual will confirm.

2 Stroke Oil:

Yamalube 2-stroke R or similar high-quality JASO FD, API TC certified 2-stroke oil. Manual will specify the exact grade and mix ratio.

Clutch Wear:

Can experience accelerated wear with aggressive riding or improper clutch use. Manual details inspection and replacement.

Piston Ring Wear:

Regular maintenance and proper pre-mix are crucial to prevent premature piston and ring wear. Manual provides wear limits and replacement procedures.

Carburetor Jetting:

May require adjustments based on altitude, temperature, and modifications. Manual provides base jetting and tuning guidance.

Suspension Seals:

Fork and shock seals can degrade over time, leading to leaks. Manual details seal replacement.

📚 Vehicle History

Yamaha Motorcycles:

Yamaha Motor Company is renowned for its extensive history in motorcycle racing, particularly in motocross, with decades of innovation and championship success.

Yz Series:

The YZ85 is a long-standing staple in Yamaha's youth motocross lineup, evolving through numerous iterations to stay competitive.

2007-2012 Generation:

This generation saw continued refinements in engine performance, chassis geometry, and suspension tuning to meet the demands of junior racers. Significant updates occurred around 2002-2005 for this platform, with incremental improvements in subsequent years.

Manufacturing Location:

Primarily manufactured in Japan. Specific assembly locations may vary by market.

🏆 Awards & Recognition

Motocross Championships:

The YZ85 platform has been a consistent performer in youth motocross racing championships worldwide, contributing to Yamaha's strong racing pedigree.

Consumer Reviews:

Generally highly rated for its performance, reliability, and competitive pricing within its class. Manuals for these bikes are essential for owners to maintain this reputation.

Emissions:

Not applicable for off-road competition vehicles in most markets. Manual will not cover emissions compliance.