Positioning:
Crucial resource for owners and technicians of the iconic Harley-Davidson FLSTF Fat Boy, offering in-depth maintenance and repair capabilities.
Value Proposition:
Provides professional-level technical information that would otherwise require expensive dealership labor or specialized knowledge.
Comprehensiveness:
Covers all aspects of the motorcycle, ensuring a complete understanding for any service task.
Accessibility:
PDF format allows for easy searching, printing of specific sections, and access on various devices.
Engine:
Twin Cam 88B, including disassembly, assembly, inspection, and specifications
Fuel System:
Carburetor (CV), fuel injection (if applicable to specific variant), fuel tank, fuel pump, fuel lines
Ignition System:
Ignition module, coils, spark plugs, wiring
Transmission:
5-speed Cruise Drive transmission, clutch, primary drive, final drive
Brakes:
Front and rear brake systems, calipers, master cylinders, brake lines, hydraulic fluid
Suspension:
Front fork (telescopic), rear shock absorbers, swingarm
Electrical System:
Wiring diagrams, lighting, starting system, charging system, battery, switches, instruments
Chassis And Frame:
Frame, steering head, wheels, tires, bearings
Bodywork:
Fenders, fuel tank, seat, handlebars, controls, exhaust system
Diagnostics:
Troubleshooting guides for common issues, fault codes (if applicable)
Maintenance:
Scheduled maintenance, oil changes, filter replacements, lubrication
Repair:
Engine rebuild, transmission overhaul, brake system repair, suspension servicing
Troubleshooting:
Systematic approach to identifying and resolving mechanical and electrical issues
Disassembly Assembly:
Step-by-step instructions for component removal and installation
Wiring Diagrams:
Detailed electrical schematics for all circuits
Specifications:
Torque values, clearances, fluid capacities, wear limits
Depth:
Comprehensive, covering routine maintenance to complete engine and transmission rebuilds
Engine Type:
Air-cooled, Twin Cam 88B V-twin
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)
Horsepower:
Approx. 65-70 HP (at crankshaft, stock tuning)
Torque:
Approx. 78-85 ft-lbs (at crankshaft, stock tuning)
Carburetor:
Keihin CV 40mm (Constant Velocity)
Fuel Type:
Unleaded gasoline, minimum 91 octane
Type:
5-speed Cruise Drive
Primary Drive:
Duplex chain, 34/46 ratio (1.353:1)
Final Drive:
Belt, 32/66 ratio (2.0625:1)
Clutch Type:
Wet, multi-plate, hydraulic actuation
Transmission Fluid Type:
Harley-Davidson Formula+ (or equivalent GL-4, 75W-85/75W-90 transmission fluid)
Primary Chain Tensioner:
Hydraulic
Length:
Approx. 93.3 in. (2370 mm)
Width:
Approx. 37.2 in. (945 mm)
Height:
Approx. 48.5 in. (1232 mm)
Wheelbase:
Approx. 64.5 in. (1638 mm)
Dry Weight:
Approx. 670 lbs (304 kg)
Gross Vehicle Weight Rating:
Approx. 1030 lbs (467 kg)
Fuel Tank Capacity:
4.0 US gallons (15.1 L)
Crash Test Results:
Not applicable for motorcycles in traditional automotive sense.
Brakes:
Dual-piston caliper front and rear brakes.
Lighting:
Halogen headlight, LED tail/brake light, bullet turn signals.
Frame Construction:
Steel, rigid backbone, dual downtube frame for stability.
Stock System:
Basic analog instrumentation (speedometer, tachometer, fuel gauge, oil pressure gauge). No integrated infotainment system on this model.
Features:
None standard on this model year; focused on traditional riding experience.
Features:
None standard; typically after-market solutions for communication or GPS.
First Service:
1000 miles (1600 km) or 6 months
Subsequent Service:
Every 5000 miles (8000 km) or 12 months thereafter
Engine Oil Type:
Harley-Davidson SYN3 (Synthetic) or equivalent SAE 20W-50 motorcycle oil
Engine Oil Capacity:
Approx. 4.0 US quarts (3.8 L) with filter change
Primary Chain Case Fluid:
Harley-Davidson Formula+ or SAE 75W-90 gear oil (API GL-4)
Primary Chain Case Fluid Capacity:
Approx. 1.0 US quart (0.95 L)
Brake Fluid Type:
DOT 4 hydraulic brake fluid
Fork Oil Type:
Refer to manual for specific weight and type (often Harley-Davidson suspension fluid or a good quality 5W-10W fork oil)
Cam Chain Tensioners:
Early Twin Cam models (pre-2007) used plastic cam chain tensioners that could wear and fail, potentially leading to engine damage. Hydraulic tensioners introduced later are more robust. This manual will detail inspection and replacement procedures.
Oil Leaks:
Potential for oil leaks from primary cover, rocker boxes, and transmission seals due to aging gaskets and seals. Manual covers gasket replacement.
Carburetor Tuning:
CV carburetor can require periodic adjustments and cleaning for optimal performance. Manual provides tuning guidelines.
Legacy:
Harley-Davidson has a rich history dating back to 1903, synonymous with American motorcycle culture and iconic V-twin engines.
Fat Boy Introduction:
The Fat Boy line debuted in 1990, known for its distinctive styling inspired by pre-WWII motorcycles, featuring wide handlebars, a teardrop tank, and solid-disc aluminum wheels.
2004 Updates:
The 2004 model continues the Fat Boy tradition, featuring the Twin Cam 88B engine and the iconic styling. Minor updates would be within the Twin Cam family evolution.
Manufacturing Location:
United States (Various Harley-Davidson assembly plants)
Model Recognition:
The Harley-Davidson Fat Boy is consistently recognized for its iconic styling and comfortable riding experience, making it a perennial favorite in the cruiser segment.
Consumer Satisfaction:
Generally high consumer satisfaction ratings for build quality and classic appeal.
Industry Standards:
Manual adheres to typical automotive service manual standards for clarity and technical accuracy.
