🏷️ Basic Information

Make:

Harley-Davidson

Model:

FLT

Year:

2005

Engine Type:

Twin Cam 88 / Twin Cam 103

Engine Code Twin Cam 88:

Engine designation for the standard 88 cubic inch variant.

Engine Code Twin Cam 103:

Engine designation for the 103 cubic inch Big Bore variant.

👋 Introduction

Positioning:

Essential technical resource for owners and mechanics of Harley-Davidson FLT models equipped with the Twin Cam 88 or Twin Cam 103 engines.

Manual Quality:

Represents the authoritative source of repair information, often exceeding the detail found in aftermarket manuals.

Uniqueness:

Focuses on the specific engineering and maintenance requirements of the iconic Twin Cam engine platform in the FLT touring chassis.

Target Audience:

Professional motorcycle technicians, experienced home mechanics, and dedicated Harley-Davidson enthusiasts.

📋 Manual Details

Primary Focus:

Repair and Service

Additional Coverage:

Maintenance, Troubleshooting, Diagnostics, Overhaul

Estimated Pages:

900-1200 pages (typical for comprehensive Harley-Davidson service manuals of this era)

Type:

Factory Service Manual (FSM) / Repair Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine Mechanical:

Cylinder heads, cylinders, pistons, crankshaft, camshafts, timing, lubrication system, cooling system (air-cooled engine management).

Fuel System:

Carburetor (Keihin CV), fuel pump, fuel lines, fuel tank, fuel filtering.

Ignition System:

Ignition module, spark plugs, ignition coils, wiring.

Electrical System:

Battery, charging system (stator, regulator/rectifier), lighting (headlight, taillight, turn signals), instrumentation, starter system, wiring diagrams.

Transmission:

Clutch, primary drive, 5-speed gearbox (internals, lubrication, adjustment).

Drivetrain:

Belt drive, rear wheel, final drive belt inspection and replacement.

Suspension:

Front fork (disassembly, oil change, seal replacement), rear shock absorbers, swingarm, bearings.

Brakes:

Front and rear brake calipers, master cylinders, brake lines, brake fluid flush and replacement, pad replacement.

Chassis And Frame:

Frame inspection, steering head bearings, wheel bearings, tire mounting and balancing.

Bodywork And Fittings:

Fairings, saddlebags, seats, fenders, fuel tank removal, controls (handlebars, levers, pedals).

Routine Maintenance:

Oil changes, filter replacements, spark plug service, air filter cleaning/replacement, brake fluid checks, drive belt tensioning.

Diagnostic Procedures:

Troubleshooting engine performance, electrical faults, and drivability issues using symptom-based diagnostics.

Disassembly And Assembly:

Detailed step-by-step instructions for major component removal and installation (engine, transmission, forks, etc.).

Rebuild Procedures:

Comprehensive guides for engine, transmission, and carburetor rebuilds.

Wiring Diagrams:

Complete and detailed electrical schematics for fault finding and component identification.

Depth:

Expert-level, covering complete overhaul and advanced diagnostics, suitable for professional technicians and experienced DIYers.

Diagnostic Tools:

May reference proprietary Harley-Davidson diagnostic tools (e.g., DigiTech) for specific electronic diagnostics.

📊 Manual Specifications

Format:

PDF

Searchability:

Typically text-searchable PDF for efficient information retrieval.

Quality:

High-resolution scans of original factory documentation, ensuring clarity of text and diagrams.

Type:

N/A (Digital PDF Download)

Type:

N/A (Digital PDF Download)

⚙️ Engine Specifications

Engine Family:

Harley-Davidson Twin Cam

Displacement Twin Cam 88:

88 cubic inches (1450cc)

Displacement Twin Cam 103:

103 cubic inches (1690cc) - typically a Big Bore kit upgrade for the Twin Cam 88.

Engine Configuration:

45-degree V-twin, overhead valves (OHV) with pushrods.

Bore Stroke Twin Cam 88:

3.75 in. x 4.00 in. (95.25 mm x 101.6 mm)

Bore Stroke Twin Cam 103:

3.875 in. x 4.375 in. (98.4 mm x 111.1 mm) - typical for 103 ci Big Bore kits.

Horsepower Twin Cam 88:

Approx. 65-70 HP (stock, estimated)

Torque Twin Cam 88:

Approx. 75-85 lb-ft (stock, estimated)

Horsepower Twin Cam 103:

Approx. 70-75 HP (stock Big Bore, estimated)

Torque Twin Cam 103:

Approx. 90-95 lb-ft (stock Big Bore, estimated)

Carburetor Model:

Keihin CV (Constant Velocity) 40mm

Fuel Delivery:

Gravity feed from fuel tank via electric fuel pump.

Fuel Type:

Unleaded gasoline, minimum 91 octane recommended for optimal performance and to prevent detonation.

🔧 Transmission

Type:

5-speed manual transmission (Harmonic Drive)

Gear Ratios:

Specific ratios detailed in manual, e.g., 1st: 9.312, 2nd: 6.481, 3rd: 4.746, 4th: 3.750, 5th: 3.175

Type:

N/A for this model year/platform from factory.

Primary Drive:

Enclosed primary drive chain with wet clutch.

Transmission Oil:

Harley-Davidson Formula Plus (or equivalent API GL-4 75W-90 or 80W-90 gear oil compatible with motorcycles).

📐 Dimensions

Model Variant:

FLT (Touring chassis)

Wheelbase:

Approx. 63.5 inches (1613 mm)

Length:

Approx. 93.5 inches (2375 mm)

Height:

Approx. 53.0 inches (1346 mm)

Dry Weight:

Approx. 700-750 lbs (318-340 kg)

Gross Vehicle Weight Rating Gvwr:

Approx. 1200 lbs (544 kg)

Payload Capacity:

Approx. 450-500 lbs (204-227 kg)

Saddlebag Capacity:

Integrated hard saddlebags, capacity varies by model variant and specific configuration.

🛡️ Safety Features

Crash Test Ratings:

Motorcycles are not subjected to formal crash test ratings like automobiles. Safety is evaluated based on component design and rider control.

Braking System:

Dual disc front brakes, single disc rear brake. ABS was not standard on most 2005 models but was an option on some.

Lighting:

Halogen headlight, LED taillight, incandescent turn signals.

Frame Construction:

Steel, double-cradle frame designed for stability.

Rider Control:

Ergonomic handlebar and seating position for rider control and comfort.

💡 Technology Features

Audio System:

Factory-installed CB radio, intercom, and AM/FM radio systems were common on FLHTCU (Ultra Classic) models. Details on operation and troubleshooting are included.

Cruise Control:

Electronic cruise control was available on many 2005 FLT models, with diagnostic and repair procedures outlined.

Diagnostic Ports:

May include basic diagnostic connectors, but extensive electronic diagnostics typically require specialized Harley-Davidson tools.

🔧 Maintenance

Initial Service:

Typically at 1,000 miles (1,600 km) - includes oil change, filter change, primary chain adjustment, clutch inspection, etc.

Subsequent Oil Change:

Every 5,000 miles (8,000 km) or annually, whichever comes first.

Spark Plug Replacement:

Every 10,000 miles (16,000 km) or as needed.

Drive Belt Inspection Tensioning:

Every 5,000 miles (8,000 km).

Brake Fluid Flush:

Every 24 months regardless of mileage.

Engine Oil:

Harley-Davidson SYN3 (synthetic) or HD 360 (conventional) 20W-50, or equivalent API CI-4 rated motorcycle oil.

Engine Oil Capacity:

Approx. 3.5 US quarts (3.3 L) with filter change for Twin Cam 88.

Primary Chain Case Oil:

Harley-Davidson Formula Plus or equivalent API GL-4 75W-90 or 80W-90 gear oil.

Primary Chain Case Oil Capacity:

Approx. 1 quart (0.95 L).

Transmission Oil:

Harley-Davidson Formula Plus or equivalent API GL-4 75W-90 or 80W-90 gear oil.

Transmission Oil Capacity:

Approx. 24 fl oz (0.7 L).

Brake Fluid:

DOT 4 or DOT 5.1 (check specific model variant or manual for definitive specification, but DOT 4 is common for this era).

Cam Chain Tensioners:

Early Twin Cam models (pre-2007) are known for wear on the hydraulic cam chain tensioner shoes, potentially leading to noise and eventual failure. The manual will detail inspection and replacement procedures.

Oil Leaks:

Common areas for leaks include primary cover gasket, transmission seal, and rocker box gaskets. The manual provides detailed steps for diagnosis and sealing.

Rear Cylinder Overheating:

Can occur in heavy traffic or hot weather due to the air-cooled nature and proximity of the rear cylinder. Proper maintenance and potentially advanced cooling solutions are covered.

Clutch Adjustment:

Requires periodic adjustment to maintain proper engagement and prevent slippage. Manual details the process.

📚 Vehicle History

Legacy:

Harley-Davidson, founded in 1903, has a long-standing legacy in motorcycle manufacturing, particularly in the cruiser and touring segments.

Flt:

The FLT designation represents Harley-Davidson's touring platform, characterized by the fairing, saddlebags, and comfortable riding position. The Twin Cam engine replaced the Evolution (Evo) engine in 1999, and the 103ci was introduced as a factory Big Bore option later in the Twin Cam's lifecycle.

Engine Introduction Twin Cam:

1999

Model Year Coverage:

The manual specifically covers 2005 FLT models, which would include variants like the FLHTC (Classic), FLHTCU (Ultra Classic Electra Glide), etc., equipped with the Twin Cam 88 and potentially the 103ci Big Bore option.

🏆 Awards & Recognition

Model Legacy:

Harley-Davidson motorcycles, particularly the touring models, are widely recognized for their comfort, long-distance capability, and iconic status.

Owner Satisfaction:

Generally high owner satisfaction for the FLT platform, praised for its touring prowess and the enduring appeal of the Twin Cam engine.

Manual Certification:

This is a factory-derived service manual, considered the definitive technical reference for the vehicle.