Market Segment:
Mid-size touring/cruiser motorcycle segment, known for BMW's engineering and reliability.
Competitors:
Honda Shadow series, Yamaha V-Star series, Kawasaki Vulcan series, Harley-Davidson Sportster (in terms of cruiser styling).
Model Strengths:
Torquey boxer-twin engine, comfortable riding position, shaft drive (low maintenance), BMW build quality, ABS availability.
Engine Mechanical:
Engine disassembly, assembly, overhaul, cylinder head, valves, pistons, crankshaft, camshaft, timing, lubrication system, cooling system (air-cooled with oil cooling).
Fuel System:
Fuel injection system (throttle body, injectors, fuel pump, fuel pressure regulator, sensors), fuel tank, fuel lines, emission controls.
Ignition System:
Ignition coils, spark plugs, crankshaft position sensor, ignition control module.
Transmission:
Clutch operation, gearshift mechanism, gearbox disassembly and assembly, lubrication.
Drivetrain:
Final drive (bevel gear housing), driveshaft, universal joints, rear wheel hub.
Suspension:
Front fork (telescopic, potentially with adjustable preload/damping for some variants), rear swingarm, shock absorber(s), linkage (if applicable).
Braking System:
Front and rear brake calipers, brake discs, master cylinders, brake lines, ABS (if equipped), brake fluid.
Electrical System:
Battery, charging system (alternator/generator, voltage regulator), starter motor, lighting (headlight, taillight, turn signals), horn, wiring diagrams, fuses, relays, ECU/control units.
Chassis Bodywork:
Frame, subframe, body panels, seat, fuel tank mounting, handlebars, controls, exhaust system.
Routine Maintenance:
Oil and filter changes, air filter replacement, spark plug checks/replacement, brake fluid flush, coolant checks (if applicable), chain/shaft drive lubrication and adjustment.
Troubleshooting:
Diagnostic procedures for common issues, fault code interpretation (if OBD system present), electrical system troubleshooting, engine performance issues.
Major Repairs:
Engine rebuilds, transmission overhauls, suspension fork rebuilds, brake system repairs, electrical component replacement.
Technical Specifications:
Torque values for fasteners, engine clearances, fluid capacities, electrical system specifications, dimensional data.
Depth Of Coverage:
Comprehensive, covering from basic rider maintenance to complete engine and transmission rebuilds. Designed for professional mechanics and skilled DIY enthusiasts.
Engine Type:
Air-cooled, four-stroke, boxer-twin (flat-twin)
Displacement:
848 cc (850cc class)
Bore X Stroke:
90.0 mm x 66.0 mm
Compression Ratio:
10.0:1
Valve Train:
SOHC, 2 valves per cylinder
Power Output:
Approximately 65 hp (48 kW) @ 6750 rpm (specifications may vary slightly by market/region)
Torque Output:
Approximately 76 Nm (56 lb-ft) @ 5500 rpm (specifications may vary slightly by market/region)
Fuel Delivery:
Electronic Fuel Injection (Bosch Motronic MA 2.4 variant likely)
Fuel Type:
Unleaded gasoline, minimum 91 RON (87 AKI)
Fuel Tank Capacity:
Approximately 20 liters (5.3 US gal)
Safety Standards:
Complies with relevant EU and US motorcycle safety regulations of the era.
ABS:
Optional BMW Motorrad Integral ABS (Anti-lock Braking System) available on some models.
Braking Performance:
Dual disc front brakes, single disc rear brake, typically with braided stainless steel lines for improved feel and durability.
Lighting:
Halogen headlight, LED taillight and indicators (common for BMW of this era), good visibility.
Chassis Design:
Steel tube frame provides rigidity and stability.
Oil Change Interval:
Typically every 10,000 km (6,000 miles) or annually, whichever comes first.
Major Service Interval:
Valve adjustment and other checks usually around 20,000 km (12,000 miles).
Engine Oil Type:
API SG/SH/SJ or higher, SAE 20W-40 or 20W-50. BMW recommends specific motorcycle-specific oils.
Engine Oil Capacity:
Approximately 3.0 liters (3.2 US quarts) with filter change.
Transmission Oil Type:
SAE 80W-90 API GL-5 gear oil.
Transmission Oil Capacity:
Approximately 0.3 liters (0.32 US quarts).
Final Drive Oil Type:
SAE 80W-90 API GL-5 gear oil.
Final Drive Oil Capacity:
Approximately 0.25 liters (0.26 US quarts).
Brake Fluid Type:
DOT 4 (or DOT 5.1 if specified for ABS models)
Common Wear Items:
Clutch plates, front fork seals, swingarm pivot bearings, exhaust header gaskets.
Electrical Reliability:
While generally robust, some older BMWs can experience aging electrical connectors or component failures (e.g., voltage regulator, starter solenoid).
Fuel System Maintenance:
Regular fuel system cleaning and injector checks can prevent performance issues.
Bmw Motorrad History:
BMW Motorrad has a long history dating back to the 1920s, renowned for engineering excellence, boxer engines, and shaft drive technology.
R Series Heritage:
The R850R/C is part of BMW's long-standing R series of boxer-twin motorcycles, evolving from earlier displacements. It offered a more accessible entry point into BMW ownership compared to the larger R1100/R1150 series.
Production Period:
The R850R series was produced from the mid-1990s through the early 2000s, with the 2004 model being one of the later iterations before being phased out or succeeded by other models.
