🏷️ Basic Information

Make:

BMW

Model:

R Series (R80, R90, R100)

Year:

1986

Engine Codes:

R100 (247)

👋 Introduction

Positioning:

Essential technical documentation for owners and technicians working on BMW's iconic boxer twin motorcycles of the era, prized for their touring capability and robust engineering.

Competitors:

Competes with other marque-specific service manuals from the period (e.g., Honda CB series, Kawasaki Z series) and generic motorcycle repair guides. This manual's strength lies in its BMW-specific detail.

Features:

Comprehensive coverage of all major mechanical and electrical systems, detailed troubleshooting procedures, and clear illustrations/diagrams. Focus on practical repair and maintenance.

📋 Manual Details

Engine Overhaul:

Complete

Transmission Repair:

Complete

Electrical System:

Comprehensive

Chassis And Suspension:

Detailed

Fuel System:

Thorough

Braking System:

Detailed

Bodywork And Frame:

Included

Maintenance Procedures:

Extensive

Troubleshooting Guides:

Detailed

Estimated Pages:

200-300 (estimated for a comprehensive workshop manual)

Type:

Workshop Repair Service Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine Mechanical:

Engine assembly, disassembly, tuning, valve adjustment, piston and cylinder inspection, crankshaft and connecting rod service.

Fuel System:

Carburetor (Bing) overhaul and adjustment, fuel pump, fuel lines, fuel tank servicing.

Ignition System:

Ignition timing, spark plugs, ignition coils, electronic ignition components (if applicable for '86 models).

Transmission And Drivetrain:

Gearbox disassembly and assembly, clutch service, final drive, driveshaft maintenance.

Electrical System:

Wiring diagrams, lighting system, battery, charging system (alternator, regulator), starter motor, instrumentation.

Braking System:

Brake fluid replacement, caliper service, master cylinder, brake line inspection and replacement.

Suspension And Steering:

Front forks (telescopic), rear swingarm and shock absorbers, steering head bearing service, wheel bearing replacement.

Bodywork And Frame:

Frame inspection, fairings, seat maintenance, fuel tank removal and installation.

Routine Maintenance:

Oil changes, filter replacements, chain adjustment (if applicable to specific sub-models), lubrication points.

Major Repairs:

Engine rebuilds, transmission overhauls, suspension component replacement, electrical component diagnosis.

Troubleshooting:

Diagnostic flowcharts for common running issues, electrical faults, and mechanical problems.

Component Testing:

Specifications and methods for testing ignition components, charging system, and fuel system parts.

Depth:

Comprehensive, suitable for both home mechanics and professional workshops. Includes detailed exploded diagrams and torque specifications.

📊 Manual Specifications

Format:

PDF

Searchable:

Yes (typically for PDF manuals)

Printable:

Yes

Quality:

High-resolution scans, ensuring clarity of diagrams and text.

Type:

N/A (Digital PDF)

Type:

N/A (Digital PDF)

⚙️ Engine Specifications

Type:

Air-cooled, four-stroke boxer twin

Displacement R80:

797.5 cc

Displacement R90:

897.2 cc (R90/6, R90S)

Displacement R100:

979.9 cc (R100/7, R100RS, R100RT, R100CS, R100GS, R100R)

Bore X Stroke R80:

82.5 mm x 74.5 mm

Bore X Stroke R90:

90 mm x 70.6 mm (R90/6, R90S)

Bore X Stroke R100:

94 mm x 70.6 mm (R100/7, R100RS, R100RT, R100CS, R100GS, R100R)

Compression Ratio Varies:

Varies by model variant (e.g., 8.2:1 to 9.5:1)

Horsepower R80:

Approx. 50 HP (37 kW) at 6500 rpm (varies)

Horsepower R90:

Approx. 65 HP (48 kW) at 7000 rpm (R90S)

Horsepower R100:

Approx. 65-70 HP (48-51 kW) at 7000-7250 rpm (varies by model)

Torque R80:

Approx. 6.2 kg⋅m (61 Nm; 45 lb⋅ft) at 5000 rpm (varies)

Torque R100:

Approx. 7.5 kg⋅m (74 Nm; 54 lb⋅ft) at 6000 rpm (varies)

Carburetors:

Typically dual Bing constant-velocity carburetors (e.g., 32mm or 40mm depending on model).

Fuel Type:

Unleaded gasoline (91 RON or higher recommended, check specific model requirements)

🔧 Transmission

Type:

5-speed manual, constant mesh gearbox with shaft drive

Type:

N/A (Shaft drive was standard)

Clutch Type:

Single dry plate clutch operated by cable

Gear Ratios:

Specific ratios vary by model and year, detailed in the manual.

Final Drive:

Bevel gear drive (shaft drive)

📐 Dimensions

Length:

Varies by model (e.g., R100RT ~2200 mm)

Width:

Varies by model (e.g., R100RS ~750 mm without mirrors)

Height:

Varies by model (e.g., R100RT ~1400 mm)

Dry Weight Approx:

R80: ~200 kg, R100 models: ~210-240 kg depending on configuration (RS, RT, GS).

Gross Vehicle Weight:

Consult specific model data sheet; typically around 400-450 kg.

Fuel Capacity:

Typically 18-24 liters (including reserve) depending on the fuel tank fitted.

🛡️ Safety Features

Crash Safety:

Not applicable for vintage motorcycle manuals in the same way as modern cars; focus is on mechanical safety and rider control.

Braking:

Disc brakes front and rear on most models; dual disc front often on R100 models. ABS was not a standard feature in 1986.

Suspension:

Responsive suspension systems contributing to stability and handling. Manual covers adjustments and maintenance.

Lighting:

Halogen headlight, taillight, brake light, turn signals. Manual details bulb types and wiring.

Frame Integrity:

Robust steel tube frame designed for longevity and stability. Manual provides inspection guidelines.

💡 Technology Features

System:

N/A (This era of motorcycles predates integrated infotainment systems. Focus is on mechanical and electrical functionality.)

Features:

N/A (No electronic driver assistance features common to modern vehicles.)

Features:

N/A (No Bluetooth, USB, or smartphone connectivity.)

Gauge Cluster:

Analog speedometer, tachometer, ammeter, and indicator lights for turn signals, oil pressure, and high beam. Manual details diagnostics for these components.

🔧 Maintenance

Oil Change Engine:

Typically every 5,000-10,000 km or annually. Manual will specify exact intervals and oil types.

Valve Adjustment:

Recommended every 10,000-15,000 km. Crucial for maintaining performance and engine longevity.

Brake Fluid Flush:

Recommended every 2 years, regardless of mileage.

Gearbox Oil Change:

Typically every 10,000-20,000 km. Manual specifies SAE grades.

Engine Oil Grade:

SAE 20W-50 or SAE 10W-40 (depending on climate and specific engine variant, consult manual for precise recommendation).

Engine Oil Capacity:

Approx. 2.5-3.0 liters (including filter, check dipstick/sight glass).

Brake Fluid Type:

DOT 4 (or DOT 3 for earlier models, verify with manual).

Gearbox Oil Grade:

SAE 90 or SAE 80W-90 gear oil.

Final Drive Oil Grade:

SAE 90 or SAE 80W-90 gear oil.

Ignition Points Wear:

Contact breaker points can wear and require adjustment or replacement. Electronic ignition conversion is a common upgrade.

Oil Leaks:

Common in older airheads, particularly around the pushrod tubes, engine cases, and gearbox output shaft seal. Manual provides seal replacement procedures.

Carburetor Sync:

Bing carburetors require regular synchronization for smooth running. Manual details the procedure and required tools.

Starter Clutch Wear:

The starter clutch mechanism can wear over time, leading to slipping. Manual covers diagnosis and repair.

📚 Vehicle History

Heritage:

BMW Motorrad has a long history of producing reliable, durable motorcycles, particularly known for its boxer engine configuration since the 1920s. This era represents the evolution of their successful 'Airhead' series.

Evolution:

The R80, R90, and R100 series evolved from earlier models like the R75/5. The '7' series (R100/7) and subsequent S, RS, RT, CS, GS, and R models in the late 70s and 80s introduced updates like larger engines, improved braking, and aerodynamic fairings, culminating in models that continued into the 1990s.

Production Period:

The 'Airhead' boxer models, including the R80, R90, and R100, were produced in various forms from the late 1960s through the mid-1990s. The 1986 models are part of the R100 family which saw significant updates through this decade.

🏆 Awards & Recognition

Awards:

While specific awards for the 1986 models are rare to cite in a manual context, the BMW R series of this era is widely recognized by enthusiasts and motorcycle publications for its durability, touring capability, and distinct engineering, often earning 'classic' or 'iconic' status.

Durability Rating:

Consistently rated highly for build quality and long-term durability by owners and vintage motorcycle experts.