Model:
R Series (R80, R90, R100)
Product Type:
Service and Repair Manual
Engine Codes:
R80/7, R90/6, R100/7, R100S, R100RT, R100RS, R100GS, R100R
Segment:
Air-cooled boxer twin motorcycles, classic European motorcycles
Competitors:
Moto Guzzi V-twin models, Harley-Davidson Big Twin, older Japanese inline-fours
Heritage:
Iconic BMW boxer engine design, robust shaft drive, touring capability, off-road prowess (GS models)
Target Audience:
BMW R Series owners, vintage motorcycle enthusiasts, DIY mechanics, restoration projects
Engine Coverage:
Complete engine overhaul, tuning, carburetor adjustment, ignition system, lubrication system
Transmission Coverage:
Gearbox overhaul, clutch replacement, shaft drive maintenance
Chassis Coverage:
Frame, suspension (front forks, rear shocks), wheels, steering, braking system (drum and disc)
Electrical Coverage:
Wiring diagrams, lighting, ignition system, battery charging, starter motor, instrumentation
Bodywork Coverage:
Fenders, fuel tank, seat, fairings (where applicable), exhaust system
Estimated Pages:
300-500 (typical for comprehensive service manuals of this era)
Type:
Factory Service Manual / Workshop Manual
Format:
Downloadable Digital File (PDF)
Engine:
Air-cooled flat-twin boxer engine (various displacements: 797cc, 897cc, 971cc, 980cc, 1000cc)
Fuel System:
Carburetor types (Dell'Orto, Bing), fuel pump, fuel lines
Ignition System:
Breaker point ignition, electronic ignition (depending on model year/variant)
Transmission:
5-speed constant mesh gearbox
Drivetrain:
Shaft drive, universal joint, final drive housing
Suspension:
Telescopic front forks (Marzocchi, Fournales on some models), dual rear shock absorbers (Koni, Bilstein, Sachs)
Brakes:
Front disc brakes (single or dual), rear drum brakes (later models may have rear disc options)
Electrical System:
12V system, dynamo/alternator, battery, starter motor, regulator/rectifier, lighting circuits, horn, indicators
Scheduled Maintenance:
Oil changes, filter replacements, spark plug checks, valve clearance adjustments, lubrication points, brake adjustments
Troubleshooting:
Diagnostic procedures for common engine, electrical, and mechanical faults
Engine Rebuild:
Piston and cylinder replacement, crankshaft and bearing service, camshaft and valve train overhaul
Transmission Repair:
Gearbox disassembly, inspection, and reassembly; clutch plate replacement
Suspension Service:
Fork seal replacement, shock absorber servicing and replacement
Brake System Maintenance:
Brake pad replacement, caliper servicing, master cylinder overhaul, brake fluid bleeding
Electrical Diagnostics:
Wiring harness inspection, component testing, fault finding using wiring diagrams
Depth:
Comprehensive from routine maintenance to full engine and gearbox rebuilds. Includes detailed torque specifications, clearances, and diagnostic procedures.
Configuration:
Air-cooled, four-stroke, horizontal-opposed twin-cylinder (Boxer)
Bore X Stroke R80:
81 mm x 70.6 mm
Bore X Stroke R90:
90 mm x 70.6 mm
Bore X Stroke R100:
94 mm x 70.6 mm (approx. 980cc for R100/7, 980cc for R100T, R100CS, R100RS, R100RT; 980cc for R100GS, R100R)
Displacement R80:
797.5 cc
Displacement R90:
897.9 cc
Displacement R100:
980.7 cc
Horsepower R80:
50 hp @ 6,500 rpm (approx.)
Horsepower R90:
60 hp @ 6,500 rpm (approx.)
Horsepower R100:
65-70 hp @ 6,250-7,000 rpm (variant dependent)
Torque R80:
55 Nm @ 5,000 rpm (approx.)
Torque R90:
70 Nm @ 5,000 rpm (approx.)
Torque R100:
74-80 Nm @ 4,500-5,000 rpm (variant dependent)
Carburetors:
Dual Dell'Orto PHM 32 A/B, or Dual Bing 54/32/34/42 (model dependent)
Fuel Type:
Unleaded gasoline (RON 91 or higher, depending on compression ratio)
Ignition Type:
Breaker point ignition (early models), Electronic ignition (later models, e.g., Motronic on some R100 models)
Length:
Variable by model (e.g., R100RT approx. 2200 mm)
Width:
Variable by model (e.g., R100RT approx. 950 mm)
Height:
Variable by model (e.g., R100RT approx. 1450 mm)
Dry Weight:
Approx. 200-230 kg (model dependent)
Gross Vehicle Weight:
Approx. 400-450 kg
Fuel Tank Capacity:
24 liters (including approx. 3-4 liter reserve)
Crash Test Data:
Not applicable (motorcycle, historical data)
Braking System:
Effective front disc and rear drum brakes (dual front discs on some sport/touring models)
Lighting:
Halogen headlight, brake light, taillight, turn signals
Frame Construction:
Robust double-cradle steel frame providing stability
Oil Change Interval:
Every 5,000 - 10,000 km or annually (refer to manual for specifics based on oil type and usage)
Valve Clearance Check:
Every 10,000 km
Spark Plug Replacement:
Every 10,000 - 20,000 km
Lubrication Points:
Regular greasing of steering head bearings, swingarm pivot, and other points as specified
Engine Oil Type:
Typically SAE 20W-40 or 20W-50 motorcycle-specific mineral or semi-synthetic oil. Consult manual for exact specifications and viscosity based on temperature range.
Engine Oil Capacity:
Approximately 2.5 - 3.0 liters (with filter change)
Gearbox Oil Type:
SAE 90 hypoid gear oil
Gearbox Oil Capacity:
Approximately 0.9 liters
Brake Fluid Type:
DOT 3 or DOT 4 brake fluid (check caliper/master cylinder for specific recommendation)
Common Faults:
Oil leaks (especially from the base of cylinders and gearbox), weak clutch springs (early models), charging system issues (rectifier/regulator), aging electrical components, carburetor synchronization challenges, worn output shaft seal.
Troubleshooting Tips:
Regularly check and top up engine oil, inspect for oil leaks, clean and synchronize carburetors, check ignition timing, maintain battery charge, inspect brake fluid level and condition.
Bmw Motorrad History:
BMW Motorrad has a long history of producing reliable and technologically advanced motorcycles, particularly known for its boxer-twin engines and shaft drive systems.
R Series Development:
The R80, R90, and R100 series represent the evolution of BMW's large displacement boxer twins, evolving from earlier 750cc and 800cc models. Key developments included engine size increases, improved braking systems, and the introduction of touring and sport-touring variants like the RT and RS, as well as the off-road capable GS models.
Production Period:
1970s - 1990s (specifically covering 1978-1996 for this manual's scope)
Manufacturing Location:
Berlin Spandau, Germany
Historical Acclaim:
The R Series is widely recognized for its durability, engineering, and timeless design, making them popular among collectors and long-distance riders.
User Reviews:
Consistently receive high praise for build quality, reliability, and unique riding character.
