🏷️ Basic Information

Make:

BMW

Model:

R100

Year:

1987

Engine Code:

R100 (Generic identifier, specific variants may exist)

Chassis Code:

R100 (Generic identifier, specific variants may exist)

👋 Introduction

Market Position:

The BMW R100 series, including the 1987 models, represented BMW's flagship air-cooled boxer motorcycles, appealing to touring riders and those seeking robust, reliable, and characterful machines. This manual targets owners and mechanics who prioritize thoroughness in maintaining and restoring these iconic bikes.

Competitive Analysis:

Competed with other large-displacement touring and sport-touring motorcycles of the era, such as Japanese inline-fours and V-twins. The R100's unique boxer engine and shaft drive offered distinct advantages in smoothness and maintenance simplicity for some riders.

Key Features:

Air-cooled boxer twin-cylinder engine, shaft drive, robust chassis, and a reputation for long-distance touring capability and reliability. This manual is essential for preserving these qualities.

📋 Manual Details

Systems Covered:

Engine, Transmission, Drivetrain, Chassis, Suspension, Brakes, Electrical System, Fuel System, Ignition System, Exhaust System, Bodywork, Troubleshooting, Maintenance

Page Count:

Estimated 300-500+ pages (typical for full service manuals)

Manual Type:

Full Service Repair Manual

Language:

English

Format:

Digital (PDF)

📖 Manual Coverage

Engine:

Detailed breakdown of twin-cylinder boxer engine, including cylinder head, valves, piston, crankshaft, camshaft, timing chain/gears, lubrication system, cooling system (air-cooled).

Transmission:

5-speed gearbox, clutch assembly, final drive, driveshaft, universal joints, gearbox oil specifications and replacement.

Drivetrain:

Rear wheel drive via enclosed driveshaft and bevel gear final drive.

Chassis:

Steel tube frame, steering head bearing, front fork (telescopic), rear swingarm, shock absorbers.

Brakes:

Front and rear disc brake systems (specific caliper types and rotor dimensions), brake fluid specifications, bleeding procedures, pad replacement.

Electrical System:

12V system, battery specifications, charging system (alternator/generator, regulator), starter motor, lighting (headlight, taillight, turn signals), ignition system (points/electronic ignition, spark plugs), instrumentation, wiring diagrams.

Fuel System:

Dual carburetors (likely Bing), fuel tank, fuel lines, fuel filter, fuel pump (if equipped), carburetor tuning and synchronization.

Ignition System:

Ignition timing, coil specifications, spark plug type and gap, troubleshooting ignition faults.

Exhaust System:

Exhaust headers, mufflers, gaskets, and proper installation.

Bodywork:

Fairing (if equipped), fuel tank, seat, fenders, side covers, cosmetic repairs and component removal/installation.

Maintenance:

Oil changes, filter replacements, chain lubrication/adjustment, tire pressure checks, brake pad inspection, spark plug replacement, battery maintenance.

Repair:

Engine rebuild (top-end and bottom-end), transmission overhaul, clutch replacement, fork seal replacement, shock absorber replacement, electrical component repair/replacement, carburetor overhaul.

Troubleshooting:

Diagnostic charts for common issues, electrical system fault finding, engine performance problems, starting issues.

Rebuild:

Comprehensive procedures for disassembling, inspecting, replacing parts, and reassembling all major mechanical and electrical components.

Refurbish:

Guidance on restoring worn components, cleaning parts, and general cosmetic improvements.

Technical Depth:

Expert level. Covers everything from basic maintenance to complete engine and transmission rebuilds, including detailed torque specifications, clearances, and diagnostic procedures.

📊 Manual Specifications

File Format:

PDF

Print Quality:

High-resolution scans for clear diagrams and text.

Binding Type:

N/A (Digital Format)

Paper Type:

N/A (Digital Format)

Searchability:

Likely searchable text within the PDF for quick information retrieval.

⚙️ Engine Specifications

Engine Type:

Air-cooled, four-stroke, boxer twin-cylinder

Displacement:

980 cc (980 cubic centimeters)

Bore X Stroke:

94 mm x 70.6 mm (approximate)

Compression Ratio:

9.5:1 (typical for R100 series)

Valve Train:

Overhead camshaft (driven by timing chain/gears), 2 valves per cylinder

Horsepower:

Approx. 70-75 HP @ 7000-7500 RPM (varies by model variant)

Torque:

Approx. 75 Nm @ 5500-6000 RPM (varies by model variant)

Carburetors:

Dual BMW/Bing carburetors (e.g., 32/36/40mm diameters depending on model variant)

Fuel Type:

Unleaded gasoline (premium recommended)

Fuel Capacity:

Approx. 20-26 Liters (depending on specific R100 model variant and tank size)

🔧 Transmission

Transmission Type:

5-speed constant mesh, sequential gearbox

Clutch Type:

Single dry plate, hydraulically operated

Final Drive:

Shaft drive with enclosed driveshaft and bevel gear final drive

Optional Gearbox:

N/A (Standard for all R100 models)

Gear Ratios:

Specific gear ratios detailed within the manual for optimal performance and efficiency.

Gearbox Oil Type:

API GL-5, SAE 75W-90 or 80W-90 gear oil recommended (specific BMW part numbers or equivalents provided in manual).

📐 Dimensions

Length:

Varies by specific R100 model (e.g., R100RT, R100RS, R100GS, R100R).

Width:

Varies by specific R100 model.

Height:

Varies by specific R100 model.

Dry Weight:

Approx. 200-240 kg (depending on model variant)

Wet Weight:

Approx. 220-260 kg (depending on model variant)

Gross Vehicle Weight Rating:

Not typically specified for motorcycles in the same way as cars, but total permissible load capacity is important.

Front Tire Size:

Typically 100/90-18 or 3.50-18 (varies by model)

Rear Tire Size:

Typically 120/90-18 or 4.00-18 (varies by model)

Wheel Type:

Cast alloy or wire-spoked wheels (depending on model variant)

Wheel Bolt Pattern:

N/A (Wheels are typically hub-mounted)

🛡️ Safety Features

Safety Ratings:

Motorcycle safety is primarily assessed through rider skill and adherence to traffic laws. Specific crash test data is generally not available for vintage motorcycles in the same format as modern cars.

Active Features:

Effective braking system (dual disc front, single disc rear), stable chassis geometry, rider control aids.

Passive Features:

Frame strength, potential for aftermarket crash protection (e.g., engine guards).

Lighting System:

Halogen headlight, taillight, brake light, turn signals.

💡 Technology Features

Infotainment System:

Basic instrumentation focused on speed, RPM, fuel level, and indicator lights. No advanced infotainment systems typical of modern motorcycles.

Driver Assistance Features:

None (Focus is on mechanical and electrical systems).

Connectivity Features:

None.

Ignition System:

Likely points ignition with mechanical advance, or early electronic ignition systems (refer to manual for exact configuration).

🔧 Maintenance

Oil Change Interval:

Typically every 5,000 - 10,000 km or annually (refer to manual for exact recommendation).

Valve Adjustment Interval:

Every 10,000 - 20,000 km (refer to manual for exact recommendation and procedure).

Spark Plug Replacement:

Every 10,000 - 20,000 km (refer to manual for correct type and gap).

Drive Shaft Lubrication:

Regular greasing of universal joints and splines is critical.

Engine Oil Type:

Viscosity typically SAE 20W-50 or 10W-40 motorcycle-specific oil (API SG or higher). Check manual for precise BMW specifications.

Engine Oil Capacity:

Approx. 2.5 - 3.0 Liters with filter change (refer to manual).

Brake Fluid Type:

DOT 3 or DOT 4 (refer to manual for specific recommendation).

Final Drive Oil Type:

API GL-5, SAE 80W-90 gear oil (refer to manual for specific BMW part numbers or equivalents).

Final Drive Oil Capacity:

Approx. 150-200 ml (refer to manual).

Known Issues:

Common issues include clutch slave cylinder leaks, final drive spline wear, carburetor synchronization drift, aging electrical connectors, and potential oil leaks from engine seals. This manual provides solutions for these and more.

📚 Vehicle History

Brand Heritage:

BMW has a long and storied history in motorcycle manufacturing, dating back to the early 20th century. Known for engineering excellence, durability, and innovation, particularly with its boxer engine configurations.

Model Evolution:

The R100 series evolved from earlier BMW boxer twins, building upon the successful R90S and R100RS/RT models. The 1987 models represent a mature iteration of this platform, with various sub-models like the R100RT (Touring), R100RS (Sport/Fairing), R100R (Roadster), and R100GS (Enduro/Adventure) offering different styles and capabilities.

Production Years:

The R100 series was produced roughly from the late 1970s through the 1990s, with 1987 being a specific model year within that range.

Manufacturing Location:

Germany

🏆 Awards & Recognition

Recognitions:

BMW motorcycles, including the R100 series, have historically received praise for their durability, engineering, and long-distance touring capabilities. While specific awards for the 1987 model year might not be readily available, the model line itself is highly regarded within the motorcycling community.

Ownership Satisfaction Ratings:

High ownership satisfaction among dedicated BMW riders for their reliability and character.

Certifications:

N/A (This refers to certifications of the manual itself, which are not applicable in this context).