Model:
R Series (R80, R90, R100)
Model Variant:
R80/7, R80RT, R90/6, R90S, R100/7, R100RT, R100RS, R100GS (likely specific to 1985 models)
Engine Code Family:
Type 247
Market Position:
Essential resource for owners and mechanics of classic air-cooled BMW motorcycles, catering to a niche but dedicated market.
Competitive Analysis:
Considered the definitive guide for these models, often surpassing OEM manuals in practical detail and clarity for repairs.
Key Features:
Detailed diagrams, step-by-step procedures, troubleshooting guides, and comprehensive specifications for the R80, R90, and R100 series motorcycles of the specified era.
Manual Type:
Service Repair Workshop Manual
Format:
Likely printed (as per typical workshop manual sales for this era), potentially also available digitally (PDF)
Applicable Models:
BMW R80 (various sub-models like R80/7, R80RT), R90 (R90/6, R90S), R100 (R100/7, R100RT, R100RS, R100GS - ensuring 1985 applicability)
Page Count:
Estimated 300-500 pages (typical for comprehensive workshop manuals of this era)
Engine:
Complete overhaul, tuning, carburetor service, ignition system, lubrication system, cooling system (air-cooled)
Transmission:
Gearbox disassembly and assembly, clutch service, drive shaft and final drive maintenance
Brakes:
Front and rear brake system service (including disc brake components), hydraulic system maintenance
Electrical:
Wiring diagrams, battery and charging system, lighting, starting system, instrumentation, electronic ignition systems
Frame And Suspension:
Front forks, rear shock absorbers, swingarm, steering head bearing, wheel bearings, frame inspection and repair
Fuel System:
Fuel tank maintenance, fuel lines, fuel pump (if applicable), carburetor service and adjustment (Bing carburetors)
Bodywork And Fittings:
Body panels, fenders, seat, handlebars, exhaust system, fairings (if applicable)
Lubrication System:
Oil pump, oil filter, oil pan, oil passages, lubrication of main bearings, connecting rod bearings, and valve train.
Routine Maintenance:
Oil changes, filter replacements, spark plug service, valve adjustments, chain lubrication and adjustment
Troubleshooting:
Diagnostic procedures for common engine, electrical, and mechanical issues
Repair And Rebuild:
Detailed step-by-step instructions for engine disassembly, transmission overhaul, brake caliper rebuild, etc.
Adjustment And Calibration:
Carburetor synchronization, ignition timing, brake lever adjustment
Special Tools:
Identification and usage of specific BMW special tools required for certain procedures
Engine Rebuild:
Complete procedures for cylinder head removal, piston replacement, crankshaft inspection, and bearing replacement.
Electrical System Repair:
Troubleshooting starter motor, alternator, regulator, and headlight/taillight circuits. Wiring harness repair and continuity testing.
Depth:
Comprehensive: Covers everything from basic maintenance to full engine and transmission rebuilds, suitable for professional mechanics and experienced DIY enthusiasts.
Diagnostics:
Detailed diagnostic flowcharts and procedures for identifying faults in engine, electrical, and mechanical systems.
File Format:
If digital: PDF. If printed: Bound booklet.
Print Quality:
High-resolution diagrams and clear text (expected for professional workshop manuals)
Binding Type:
Stapled or saddle-stitched for smaller sections, perfect bound or spiral bound for larger volumes (if printed)
Paper Type:
Durable, possibly gloss or semi-gloss paper to withstand workshop conditions (if printed)
Completeness:
Comprehensive: Covers all aspects of service, repair, maintenance, and troubleshooting for the specified models and year. Includes detailed specifications, diagrams, and exploded views.
Engine Type:
Air-cooled, four-stroke, horizontally opposed twin-cylinder ('boxer')
Engine Displacement:
R80: ~797.5cc, R90: ~897.7cc, R100: ~979.7cc
Bore X Stroke:
Varies by model (e.g., R100: 94mm x 70.6mm, R80: 82mm x 74.5mm)
Compression Ratio:
Varies by model and specific variant (typically 9.0:1 to 10.25:1)
Valve Train:
Overhead valves (OHV) operated by pushrods and rocker arms.
Horsepower:
R80: ~50 HP, R90: ~60 HP, R100: ~65-70 HP (approximate, varies by model and tuning)
Torque:
Varies by model, but known for strong mid-range torque.
Torque Figures:
R100 models generally produce around 75-80 Nm of torque. R90 models around 70-75 Nm. R80 models around 60-65 Nm.
Carburetor Type:
Typically dual Bing carburetors (e.g., Bing 32/40/64, Bing 40/50/402)
Fuel Type:
Unleaded gasoline (premium recommended)
Carburetor Tuning:
Detailed instructions for idle speed adjustment, mixture screw setting, jetting recommendations for different altitudes/conditions, and synchronization.
Ignition Type:
Electronic Ignition (Bosch or BMW proprietary systems from this era)
Wheelbase:
Varies slightly by model, approx. 1450mm - 1480mm
Seat Height:
Varies by model, typically around 780mm - 820mm
Dry Weight:
R80/7: ~197 kg, R90/6: ~200 kg, R100RT: ~235 kg (approximate, varies significantly by model variant)
Fuel Capacity:
Typically 17-24 liters depending on tank size and model
Safety Ratings:
N/A (Motorcycle safety is assessed differently from cars, no standardized ratings like NCAP)
Active Safety:
Effective dual-disc front brakes, single rear disc (on most models), well-balanced chassis.
Passive Safety:
Robust frame construction, rider protection elements (e.g., fairings, crash bars on some models).
Oil Change Interval:
Typically every 5,000 - 10,000 km or annually, depending on usage and oil type.
Valve Adjustment Interval:
Every 10,000 km or as per manual recommendation.
Spark Plug Replacement:
Every 10,000 - 20,000 km, depending on type and condition.
Engine Oil Type:
SAE 20W-50 or SAE 15W-50 motorcycle-specific oil (check manual for exact viscosity based on climate).
Gearbox Oil Type:
Hypoid gear oil, SAE 80W-90.
Final Drive Oil Type:
Hypoid gear oil, SAE 80W-90.
Brake Fluid Type:
DOT 4 brake fluid.
Coolant Type:
N/A (Air-cooled engines)
Common Issues:
Leaking pushrod seals, worn clutch plates, carburetor synchronization issues, potential for cylinder base gasket leaks, aging electrical connectors.
Maintenance Focus:
Regular valve adjustments, proper carburetor tuning, and timely replacement of aging rubber components are key to longevity.
Brand Heritage:
BMW Motorrad has a long history of producing durable, reliable, and technically advanced motorcycles, particularly known for their boxer engines and shaft drive.
Model Evolution:
The R80, R90, and R100 models represent the evolution of BMW's boxer platform throughout the 1970s and 1980s, building upon the legacy of earlier models like the R75/5.
Production Period:
These models were produced for a significant period, with the R100 line continuing into the mid-1990s. The 1985 model year represents a mature iteration of these designs.
