🏷️ Basic Information

Make:

BMW

Model:

R80 GS / R100 GS

Model Variant:

R80 GS, R100 GS

Year:

1988

Chassis Code Prefix:

247

👋 Introduction

Segment:

Dual-purpose adventure touring motorcycles.

Reputation:

Iconic and highly capable off-road and long-distance touring machines known for their durability and ruggedness.

Competitors Era:

Honda Transalp, Yamaha Tenere, Suzuki DR Big, Kawasaki KLR.

Engine Type:

Air-cooled, twin-cylinder Boxer engine.

Suspension Front Type:

Telescopic forks (some later models may feature Monolever, though the 1988 R100 GS primarily used a conventional fork, and R80GS also used conventional forks).

Suspension Rear Type:

Monolever single-sided swingarm.

Drive Type:

Shaft drive.

Fuel Delivery:

Dual Bing carburetors.

📋 Manual Details

Engine:

Yes

Transmission:

Yes

Electrical System:

Yes

Suspension:

Yes

Brakes:

Yes

Fuel System:

Yes

Cooling System:

Yes (Air-cooled)

Frame Chassis:

Yes

Bodywork:

Yes

Troubleshooting:

Yes

Estimated Pages:

N/A (Digital PDF)

Type:

Service Repair Workshop Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine Mechanical:

Full disassembly, inspection, repair, and reassembly of engine components (pistons, rings, cylinders, crankshaft, camshafts, valves, timing chain, etc.).

Engine Management:

Carburetor adjustment, synchronization, and overhaul (Bing carburetors common to these models). Ignition system (points, coils, spark plugs).

Transmission Gearbox:

Maintenance, repair, and overhaul of the 5-speed gearbox, including clutch inspection and replacement, gear selection mechanisms.

Drive Shaft:

Drive shaft and final drive maintenance, lubrication, and inspection.

Suspension Front:

BMW Telelever or conventional telescopic fork maintenance, seal replacement, oil changes, adjustment procedures.

Suspension Rear:

Monolever rear suspension system, shock absorber overhaul/replacement, linkage maintenance.

Brakes Front:

Brake caliper servicing, pad replacement, hydraulic system bleeding, master cylinder inspection.

Brakes Rear:

Brake drum or disc inspection and maintenance, linkage lubrication.

Electrical Lighting:

Headlight, taillight, turn signals, and instrument cluster maintenance and troubleshooting.

Electrical Battery:

Battery charging system (alternator/generator), starter motor, wiring diagrams.

Electrical Ignition:

Ignition timing, spark plug types, coil specifications.

Fuel System Carb:

Detailed settings, jetting, and maintenance for Bing carburetors.

Fuel System Tank:

Fuel tank removal, installation, and cleaning.

Chassis Frame:

Frame inspection, alignment checks, and repair procedures.

Wheels Tires:

Wheel bearing maintenance, tire pressure specifications, spoke tensioning.

Body Panels:

Fairing, tank, seat, and fender removal and installation.

Routine Maintenance:

Oil changes, filter replacements, spark plug checks, chain adjustment, brake fluid flush, battery care.

Engine Rebuild:

Complete step-by-step instructions for engine overhaul and component replacement.

Carburetor Tuning:

Detailed procedures for adjusting and synchronizing carburetors.

Suspension Overhaul:

Front fork and rear shock absorber servicing.

Brake System Repair:

Brake bleeding, pad/shoe replacement, caliper/master cylinder servicing.

Electrical Diagnostics:

Troubleshooting common electrical faults using wiring diagrams.

Clutch Replacement:

Step-by-step guide for clutch plate replacement.

Wheel Bearing Service:

Inspection, cleaning, repacking, and replacement of wheel bearings.

Torque Specifications:

Detailed torque values for critical fasteners.

Depth:

Comprehensive, covering routine maintenance to complete engine and transmission rebuilds. Includes diagnostic procedures and troubleshooting charts.

📊 Manual Specifications

Format:

PDF

Searchability:

Likely text-searchable PDF, allowing for quick information retrieval.

Quality:

N/A (Digital Download)

Type:

N/A (Digital Download)

Type:

N/A (Digital Download)

⚙️ Engine Specifications

Engine Type:

Air-cooled, four-stroke, boxer twin-cylinder engine.

Displacement R80:

797.5 cc

Displacement R100:

979.5 cc

Bore X Stroke R80:

81 mm x 76 mm

Bore X Stroke R100:

94 mm x 70.8 mm

Compression Ratio R80:

8.2:1

Compression Ratio R100:

8.5:1

Horsepower R80:

50 hp (37 kW) at 6,500 rpm

Horsepower R100:

65 hp (48 kW) at 7,000 rpm

Torque R80:

57 Nm (42 lb-ft) at 5,000 rpm

Torque R100:

74 Nm (55 lb-ft) at 5,500 rpm

Carburetor:

2 x Bing 94/40 carburetors

Fuel Type:

Unleaded gasoline, minimum 91 octane

Oil Capacity With Filter:

Approx. 3.0 liters (3.2 US qt)

Oil Type:

API SG or higher, SAE 20W-50 recommended (refer to manual for specific conditions).

Ignition Type:

Electronic ignition with dual spark plugs per cylinder

🔧 Transmission

Type:

5-speed constant mesh gearbox

Drive Type:

Shaft drive to rear wheel

Clutch Type:

Single dry plate, diaphragm spring clutch

Final Drive Ratio:

3.00:1 (3.00 / 1.00) for most GS models

Gearbox Oil:

SAE 90 hypoid gear oil (refer to manual for API GL classification)

📐 Dimensions

Length Approx:

2220 mm (87.4 in)

Width Approx:

920 mm (36.2 in)

Height Approx:

1350 mm (53.1 in)

Dry Weight R80:

Approx. 190 kg (419 lbs)

Dry Weight R100:

Approx. 195 kg (430 lbs)

Gross Vehicle Weight Rating Gvwr:

Not typically specified for this era of motorcycle, but rider + luggage capacity is significant.

Fuel Tank Capacity:

26 liters (6.9 US gal), including a 5-liter reserve

Front Wheel Size:

2.50 x 19

Rear Wheel Size:

4.00 x 17

Front Tire Size:

90/90-19 (or 3.00-19)

Rear Tire Size:

130/80-17 (or 4.00-17)

Wheel Bolt Pattern:

N/A (Spoked wheels with axle mounting)

🛡️ Safety Features

Crash Test Ratings:

N/A (Motorcycles are not subject to automotive crash test ratings in the same manner).

Braking System:

Dual front disc brakes, rear drum brake (some R100GS may have rear disc). ABS was not an option for this model year.

Lighting:

Halogen headlight, integrated turn signals, stop/tail light.

Frame Construction:

Robust tubular steel frame designed for durability and off-road use.

💡 Technology Features

System:

N/A (This era of motorcycle predates integrated infotainment systems).

Features:

N/A (No electronic rider aids like ABS, traction control, or rider modes were standard).

Features:

N/A (No onboard computers or Bluetooth connectivity).

🔧 Maintenance

Oil Change Interval:

Every 5,000 km (3,000 miles) or annually. Refer to manual for specific recommendations based on usage.

Valve Adjustment Interval:

Every 10,000 km (6,000 miles) or as needed based on noise. Manual provides detailed procedure and clearances.

Spark Plug Replacement Interval:

Every 10,000 km (6,000 miles) or as needed. Check gap regularly.

Brake Fluid Flush Interval:

Every 2 years or as per manual recommendations. Inspect fluid condition regularly.

Drive Shaft Lubrication Interval:

Every 10,000 km (6,000 miles) or when specified in manual.

Engine Oil Type:

API SG or higher, SAE 20W-50 (refer to manual for operating temperature ranges).

Gearbox Oil Type:

SAE 90 hypoid gear oil (API GL-4 or GL-5, check manual for specifics).

Front Fork Oil Type:

Specific fork oil weight and type as per manual (typically SAE 15W or 20W).

Brake Fluid Type:

DOT 4 hydraulic brake fluid.

Common Wear Items:

Clutch wear, alternator brushes, starter motor solenoid, fuel line deterioration, rear shock absorber (especially older ones).

Potential Engine Issues:

Oil leaks from base gasket or cylinder head covers, valve guide wear over high mileage.

Potential Electrical Issues:

Aging wiring harness, rectifier/regulator failure, points contact issues (if not converted to electronic ignition).

Suspension Issues:

Worn fork seals, leaking rear shock absorber.

📚 Vehicle History

Heritage:

BMW Motorrad has a long history of producing robust and reliable motorcycles, with the boxer engine configuration dating back to the early days of motorcycling.

Gs Lineage:

The R80 G/S (Gelände/Straße - Terrain/Street) was introduced in 1980, creating the adventure touring segment. The R100 GS, introduced in 1987, was the larger-displacement evolution of this concept, building on the success of the R80 G/S and R65GS.

1988 Updates:

The 1988 model year saw the R100 GS receive updates including a larger 26-liter fuel tank, improved suspension (especially the Monolever rear), and revised ergonomics for better long-distance comfort and off-road capability compared to its predecessors.

Production Period Gs:

The R80 GS was produced from 1980-1987. The R100 GS was produced from 1987-1996. The 1988 model year represents an early iteration of the highly successful R100 GS.

Manufacturing Location:

Berlin, Germany

🏆 Awards & Recognition

Segment Creation:

The R80 G/S (predecessor) is widely credited with inventing the adventure touring motorcycle segment.

Longevity Reputation:

These models are renowned for their longevity and ability to be repaired and maintained by owners, contributing to their enduring popularity and value.