Target Audience:
Professional motorcycle technicians, experienced DIY mechanics, and BMW enthusiasts seeking in-depth knowledge of their R850 R850C.
Manual Value Proposition:
Offers factory-level diagnostic and repair information, crucial for maintaining the performance and longevity of these German-engineered motorcycles. Superior to generic online guides or simplified repair manuals.
Manual Advantages:
Directly addresses the specific needs of the R850 R850C models across their initial production years, providing critical data often missing in broader manuals. PDF format ensures easy access and searchability.
Engine Systems:
Engine mechanical (cylinder head, valve train, pistons, crankshaft, connecting rods), fuel injection system (Motronic, injectors, fuel pump, throttle body), ignition system, lubrication system (oil pump, oil filter, oil passages), cooling system (oil cooling components), exhaust system, engine management system diagnostics.
Transmission Drivetrain:
Clutch (operation, maintenance, replacement), gearbox (internal components, shift mechanism, bearings), final drive (shaft drive, universal joint, final drive housing, lubrication).
Electrical Systems:
Wiring diagrams, battery, starter motor, alternator, lighting system (headlight, taillight, turn signals), instrumentation, electronic control units (ECUs), sensors, actuators, starter interlock system, ABS system (if equipped).
Chassis Suspension Brakes:
Frame, front fork (telescopic, adjustment, seals), rear suspension (Monolever or Paralever depending on specific R850 model variant, shock absorber, linkage), wheel bearings, brake system (hydraulic circuits, master cylinders, brake calipers, brake pads, brake discs, ABS components), parking brake.
Bodywork Controls:
Body panels, fairings, fuel tank, seat, handlebars, control cables, footrests, stands (center stand, side stand), mirrors.
Maintenance Procedures:
Routine inspections, oil and filter changes, spark plug replacement, air filter cleaning/replacement, brake fluid flush and bleed, clutch adjustment, chain maintenance (if applicable to specific model), tire pressure checks, battery maintenance.
Repair Procedures:
Engine disassembly and reassembly, transmission overhauls, suspension component replacement, brake system repairs, electrical component testing and replacement, bodywork repairs, fuel system cleaning and component replacement.
Troubleshooting Diagnostics:
Systematic diagnostic procedures for common faults, fault code interpretation (if applicable to Motronic system), electrical system troubleshooting using wiring diagrams, mechanical component diagnosis.
Depth Of Coverage:
Comprehensive; covers everything from basic maintenance to complete engine and transmission rebuilds. Includes detailed exploded diagrams and torque specifications.
Engine Type:
Air-cooled, four-stroke, boxer-twin cylinder
Engine Displacement:
848 cc (approx.)
Bore X Stroke:
90.0 mm x 66.0 mm (typical for R850 variant)
Compression Ratio:
9.8:1 (typical)
Valve Train:
2 valves per cylinder, pushrod-actuated overhead valves (OHV)
Horsepower:
Approx. 70-74 hp @ 7250 rpm (variant dependent)
Torque:
Approx. 77-80 Nm @ 5000 rpm (variant dependent)
Fuel Delivery:
Bosch Motronic Electronic Fuel Injection (EFI)
Fuel Type:
Unleaded gasoline, minimum 91 octane (RON+MON)/2 / 87 AKI
Engine Control Unit:
Bosch Motronic (specific model variant dependent, e.g., M2.4, M2.7)
Cooling Method:
Air cooling, with supplemental oil cooler
Safety Standards:
Compliance with contemporary European and US motorcycle safety regulations of the late 1990s.
Braking System:
BMW Motorrad Integral ABS (optional on some models), dual disc front brakes, single disc rear brake.
Lighting:
Halogen headlight, LED taillight (standard), turn signal indicators.
Chassis Design:
Steel tube frame, designed for stability and rider confidence.
Instrumentation:
Analog speedometer and tachometer, digital odometer, trip meter, fuel level indicator, clock, warning lights for oil pressure, battery charge, neutral, high beam, turn signals, and ABS.
ABS System:
BMW Motorrad Integral ABS, a sophisticated anti-lock braking system for its era, enhancing safety under braking. Manual details its operation and servicing.
Diagnostic Interface:
Diagnostic capabilities via the Motronic system, accessible with specialized BMW diagnostic tools (covered conceptually in the manual for technician use).
Oil Change Interval:
Typically every 10,000 km (6,000 miles) or annually, whichever comes first. Consult manual for precise interval.
Valve Adjustment Interval:
Typically every 20,000 km (12,000 miles). Requires careful checking of clearances and adjustment.
Spark Plug Replacement:
Refer to manual; often around 20,000-30,000 km (12,000-18,000 miles).
Engine Oil Type:
BMW recommends specific synthetic or semi-synthetic motorcycle oil meeting API SG/SH or higher, with viscosity typically SAE 15W-40 or 20W-50 depending on climate. Consult manual for exact BMW specifications (e.g., BMW Motor Oil Special).
Engine Oil Capacity:
Approx. 3.0 liters (3.2 US quarts) with filter change. Verify in manual.
Brake Fluid Type:
DOT 4, low viscosity, conforming to BMW specifications. Frequent flushing is recommended.
Final Drive Oil Type:
Typically SAE 75W/90 GL-5 gear oil. Capacity approximately 0.25 liters. Verify in manual.
Common Wear Items:
Clutch plates (especially with spirited riding), wheel bearings, fork seals, exhaust system components (corrosion), ABS sensor rings.
Electrical Gremlins:
Occasional issues with wiring harness connections, particularly under the fuel tank or in the main harness, can manifest as intermittent faults. Fuel pump issues can also arise with age.
Engine Management:
Motronic system is generally robust but can be sensitive to voltage fluctuations or failing sensors (e.g., throttle position sensor, lambda sensor). Regular diagnostics are beneficial.
