🏷️ Basic Information

Make:

Harley-Davidson

Model:

FLSTF Fat Boy

Model Variant:

Fat Boy ST

Year:

2005

Chassis Code:

FLSTF

👋 Introduction

Market Segment:

Cruiser Motorcycle segment, specifically targeting riders who value iconic styling, comfortable cruising, and substantial presence.

Competitors 2005:

Other large-displacement V-twin cruisers such as Indian Chief, Victory Kingpin, and custom-styled motorcycles from various manufacturers.

Styling:

Recognizable teardrop fuel tank, wide handlebars, broad front tire, chrome accents, and a classic, muscular silhouette.

Ride Comfort:

Forward-mounted rider footpegs, low seat height, and swept-back handlebars contribute to a relaxed riding posture suitable for long-distance cruising.

📋 Manual Details

Primary Coverage:

Engine, Transmission, Chassis, Electrical, Bodywork, Suspension, Brakes, Fuel System, Ignition System, Drivetrain, Wheels and Tires, Accessories, Troubleshooting, Maintenance

Estimated Page Count:

Approximately 500-700 pages (typical for Harley-Davidson factory service manuals)

Manual Type:

Workshop Repair Service Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine:

Detailed breakdown of Twin Cam 88 engine, including carburetor systems, ignition timing, valve adjustments, piston and cylinder assembly, lubrication, cooling (air-cooled), and performance tuning. Covers both standard and SE (Screamin' Eagle) variations if applicable for the model year.

Transmission:

Service and repair procedures for the 5-speed Cruise Drive transmission, including clutch operation, gear shifting mechanisms, gearbox disassembly and reassembly, lubrication, and troubleshooting of shifting issues.

Electrical:

Comprehensive wiring diagrams, component testing, troubleshooting of electrical faults, starter system, charging system (alternator, regulator), battery service, lighting systems (headlight, taillight, indicators), ignition system diagnostics, and accessory wiring.

Chassis Suspension Brakes:

Frame and bodywork disassembly/reassembly, fork servicing, rear shock absorber replacement and adjustment, wheel bearing maintenance, brake system overhaul (hydraulic front and rear brakes), caliper service, rotor inspection, and bleeding procedures.

Maintenance:

Regular scheduled maintenance tasks, including oil changes, filter replacements (oil, air), spark plug replacement, chain/belt adjustment and lubrication, brake pad inspection, tire pressure checks, and battery maintenance.

Troubleshooting:

Systematic diagnostic procedures for common and uncommon issues, fault code interpretation (if applicable to the era), symptom-based troubleshooting guides for engine performance, electrical gremlins, and handling problems.

Repair Rebuild:

Detailed step-by-step instructions for component removal, disassembly, inspection, repair, and reassembly, covering engine internal components, transmission internals, suspension components, and brake assemblies.

Depth Of Information:

Expert level. Covers everything from basic rider maintenance to complete engine and transmission rebuilds, including torque specifications, special tool requirements, and diagnostic procedures.

📊 Manual Specifications

File Format Details:

High-resolution PDF, optimized for digital viewing and printing. Typically includes searchable text for easy navigation.

Print Quality:

Professional quality, with clear diagrams, schematics, and photographs/illustrations.

Binding Type:

N/A (Digital PDF format)

Paper Type:

N/A (Digital PDF format)

⚙️ Engine Specifications

Engine Type:

Air-cooled, 45-degree V-twin, Twin Cam 88 Engine

Displacement:

1450cc (88 cubic inches)

Bore X Stroke:

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

Compression Ratio:

8.8:1 (typical for Twin Cam 88)

Horsepower:

Approximately 65-70 HP (estimated, actual may vary slightly by tuning)

Torque:

Approximately 85-90 lb-ft (estimated, actual may vary slightly by tuning)

Fuel Delivery:

Carburetor (likely Keihin CV 40mm)

Fuel Type:

Unleaded Gasoline, minimum 91 octane recommended

Ignition Type:

Electronic Ignition (CDI)

Oil Type:

Harley-Davidson Genuine V-Twin Synthetic Oil or equivalent (e.g., SAE 20W-50)

Oil Capacity:

Approximately 3.0-3.5 quarts (2.8-3.3 liters) with filter change

Cooling Method:

Air-cooled

🔧 Transmission

Transmission Type:

5-speed Cruise Drive Manual Transmission

Optional Transmissions:

N/A for this model year and variant

Clutch Type:

Wet, multi-plate, diaphragm spring

Final Drive:

Belt Drive

Transmission Oil Type:

Harley-Davidson Formula + Transmission and Primary Chaincase Lubricant or equivalent

Transmission Oil Capacity:

Approximately 2.8 quarts (2.6 liters)

📐 Dimensions

Length:

Approximately 93.5 inches (2375 mm)

Width Handlebars:

Approximately 37 inches (940 mm)

Height Seat:

Approximately 27.0 inches (685 mm)

Ground Clearance:

Approximately 4.5 inches (115 mm)

Dry Weight:

Approximately 630 lbs (286 kg)

Gross Vehicle Weight Rating Gvwr:

Approximately 1000 lbs (454 kg)

Front Tire Size:

130/90B16

Rear Tire Size:

150/80B16

Front Wheel Type:

Chrome steel laced wheel with solid disc

Rear Wheel Type:

Chrome steel laced wheel with solid disc

Wheelbase:

Approximately 63.7 inches (1618 mm)

🛡️ Safety Features

Crash Test Ratings:

Motorcycles are not typically rated by agencies like NHTSA in the same way as cars.

Brakes:

Dual front disc brakes, single rear disc brake. Hydraulic actuation.

Lighting:

Halogen headlight, LED taillight, amber front and rear turn signals.

Frame Construction:

Steel frame and swingarm designed for stability and predictable handling.

Seatbelt:

N/A (Motorcycle)

💡 Technology Features

Audio System:

Optional auxiliary audio input or aftermarket stereo systems common for this era, though not standard factory-integrated.

Electronic Aids:

Limited electronic rider aids typical for 2005; primarily focused on mechanical systems rather than advanced electronics.

Connectivity Features:

N/A (No built-in Bluetooth or smartphone integration).

🔧 Maintenance

First Service:

1,000 miles (1,600 km) or 6 months, whichever comes first.

Subsequent Service:

Every 5,000 miles (8,000 km) or 12 months thereafter.

Oil Change Interval:

Every 5,000 miles (8,000 km) or 12 months (refer to manual for specific oil type recommendations).

Spark Plug Replacement:

Typically every 10,000 - 15,000 miles (16,000 - 24,000 km).

Belt Inspection Tension:

Inspect and adjust belt tension every 5,000 miles (8,000 km).

Engine Oil:

Harley-Davidson Genuine V-Twin Synthetic Oil 20W-50, or API SG or SH rated petroleum-based oil with a viscosity index of 120 minimum.

Primary Chaincase Oil:

Harley-Davidson Formula + Transmission and Primary Chaincase Lubricant.

Brake Fluid:

DOT 4 Hydraulic Brake Fluid.

Cam Chain Tensioner:

Early Twin Cam 88 engines (pre-2007) had plastic cam chain tensioners that could wear and require replacement. The manual will detail inspection and replacement procedures.

Carburetor Tuning:

Proper adjustment of the Keihin CV carburetor is crucial for optimal performance and fuel economy. The manual covers diagnostic and adjustment procedures.

Oil Leaks:

As with many air-cooled V-twins, minor oil seepage from gaskets and seals can occur over time. The manual guides in identifying and rectifying common leak points.

📚 Vehicle History

Brand Establishment:

Harley-Davidson Motor Company founded in 1903, a storied American manufacturer known for its V-twin motorcycles and distinct rider culture.

Fat Boy Introduction:

The Fat Boy model was introduced in 1990 and quickly became an icon for its distinctive styling, which drew inspiration from post-WWII Harley-Davidson models like the EL Hydra-Glide. The 2005 model represents a mature iteration of this design.

Manufacturing Location:

Milwaukee, Wisconsin, USA and York, Pennsylvania, USA (typical for Harley-Davidson).

Production Period:

The FLSTF Fat Boy was in continuous production through the 2005 model year, with various updates to the Twin Cam engine and chassis components over the years.

🏆 Awards & Recognition

Model Awards:

While specific awards for the 2005 FLSTF Fat Boy are not widely publicized, the Fat Boy model consistently receives accolades for its iconic styling and enduring popularity within the cruiser market. Often cited in 'best cruiser' lists for its era.

Reliability Perception:

Harley-Davidson motorcycles of this era are generally regarded for their robust mechanicals, though regular maintenance is key to longevity. The Twin Cam 88 is a well-proven engine platform.