Target Audience:
BMW R80 motorcycle owners and enthusiasts seeking to perform their own maintenance, repairs, and restorations.
Manual Value:
Provides essential technical information often unavailable or fragmented elsewhere, crucial for preserving the value and functionality of a classic motorcycle.
Comprehensiveness:
Claims to contain 'everything you will ever need' for repair, maintenance, rebuilding, refurbishing, and restoration, indicating a high degree of detail.
Diagnostic Coverage:
Mentions 'All diagnostic and...', suggesting detailed troubleshooting procedures are included.
Engine:
Comprehensive engine overhaul, including cylinder head, pistons, crankshaft, camshaft, valve train, lubrication system, and cooling (air-cooled).
Transmission:
Detailed procedures for gearbox removal, disassembly, inspection, repair, and reassembly, including clutch and final drive.
Chassis And Frame:
Frame inspection, steering head bearing service, fork assembly, rear suspension components (shock absorbers, swingarm), and wheel bearings.
Brakes:
Front and rear brake system overhaul, including caliper service, brake pad replacement, master cylinder rebuild, and bleeding procedures. Likely covers drum brakes if applicable to certain models/years.
Electrical System:
Wiring diagrams, ignition system troubleshooting, charging system (alternator, rectifier/regulator), lighting, starter motor, and battery maintenance.
Fuel System:
Carburetor disassembly, cleaning, adjustment, and synchronization (likely Bing carburetors). Fuel tank, fuel lines, and petcock service.
Bodywork And Trim:
Fender removal/installation, fuel tank mounting, seat removal, and general body panel adjustments.
Basic Maintenance:
Oil changes, filter replacement, spark plug service, air filter cleaning/replacement, chain adjustment and lubrication.
Troubleshooting:
Diagnostic procedures for common starting issues, running problems, electrical faults, and braking inefficiencies.
Repair And Rebuild:
Detailed step-by-step instructions for overhauling major components like the engine, gearbox, and suspension.
Adjustments:
Valve clearance adjustments, carburetor synchronization, clutch lever adjustment, and ignition timing setup.
Depth Level:
Comprehensive: Covers everything from routine maintenance to complete engine and gearbox rebuilds, suitable for both novice and experienced mechanics.
Engine Type:
Air-cooled, four-stroke, boxer-twin engine.
Displacement:
797.5 cc (48.68 cu in)
Bore X Stroke:
82 mm x 75 mm (3.23 in x 2.95 in)
Compression Ratio:
Approximately 8.2:1 to 9.0:1 (depending on specific R80 variant)
Cylinder Head Design:
Overhead valve (OHV) with pushrods and rockers.
Horsepower Output:
Approximately 50-55 hp (37-41 kW) at 6,200 rpm (varies slightly by model year and tune).
Torque Output:
Approximately 60-64 Nm (44-47 lb-ft) at 4,000 rpm (varies).
Carburetion:
Typically twin Bing constant-velocity (CV) carburetors, often 32mm or 40mm diameter (e.g., Bing 94/40/101 or similar).
Fuel Type:
Unleaded gasoline (premium recommended, octane rating 91-95 RON).
Oil Type:
SAE 20W-50 or SAE 10W-40 motorcycle-specific oil (mineral or semi-synthetic).
Oil Capacity:
Approximately 2.5 - 3.0 liters (2.6 - 3.2 US qt) with filter change.
Gearbox Type:
5-speed constant-mesh manual gearbox.
Optional Gearbox:
N/A for this era/model. Standard 5-speed was universal.
Clutch Type:
Single dry plate diaphragm spring clutch.
Final Drive:
Shaft drive with bevel gear final drive housing.
Gearbox Oil Type:
SAE 90 hypoid gear oil (API GL-4).
Gearbox Oil Capacity:
Approximately 0.65 liters (0.69 US qt).
Wheelbase:
Approximately 1,460 mm (57.5 in).
Seat Height:
Approximately 780 mm (30.7 in).
Dry Weight:
Approximately 190-200 kg (419-441 lbs) depending on configuration.
Fuel Tank Capacity:
Approximately 18 liters (4.75 US gal), including a 3-liter reserve.
Safety Certifications:
N/A (Motorcycle safety standards differ from automotive; focus on mechanical integrity and braking performance).
Braking System:
Front: Dual disc brakes with hydraulic actuation. Rear: Drum brake or disc brake depending on specific R80 model variant (e.g., R80/7, R80G/S).
Suspension Type:
Front: Telescopic fork. Rear: Swingarm with dual shock absorbers.
Frame Construction:
Steel tube frame (double cradle).
Oil Change Interval:
Every 5,000 km (3,000 miles) or annually, whichever comes first.
Valve Adjustment Interval:
Every 10,000 km (6,000 miles).
Spark Plug Replacement:
Every 10,000 km (6,000 miles).
Carburetor Sync Interval:
Recommended every 10,000 km (6,000 miles) or as needed for smooth running.
Engine Oil Spec:
SAE 20W-50 API SG or higher motorcycle-specific oil.
Gearbox Oil Spec:
SAE 90 GL-4 hypoid gear oil.
Brake Fluid Spec:
DOT 3 or DOT 4 hydraulic brake fluid.
Final Drive Oil Spec:
SAE 90 GL-4 hypoid gear oil (same as gearbox).
Typical Wear Items:
Steering head bearings, wheel bearings, swingarm pivot bearings, brake pads/discs, exhaust system gaskets.
Common Faults:
Carburetor wear (leading to poor idle/off-idle performance), oil seal leaks (engine crankcase, gearbox output), electrical connections degradation, starter clutch wear.
Bmw Motorcycle Legacy:
BMW's long-standing reputation for robust engineering, reliability, and shaft-driven motorcycles dates back to the early 20th century. The boxer-twin platform is a cornerstone of their motorcycle history.
R80 Lineage:
The R80 series evolved from earlier BMW Boxer models (like the R75/7) and served as a popular touring and everyday motorcycle, bridging the gap between the R75 and the larger R100 models. Introduced in 1977 as the R80/7.
Production Period:
The R80 series was produced through the late 1970s and 1980s, with the R80/7 being the initial iteration, followed by variants like the R80G/S (dual-sport) and R80ST.
