Harley-Davidson Fat Boy (117 cui) (2025) — Specs
Identity
Manufacturer: Harley-Davidson
Model: Fat Boy (117 cui)
Category: Cruiser
Type: Motorcycle
Years: 2025 →
Engine
Displacement (cc): 1923
Cylinders: 2
Power (hp): 104
Power (kW): 77
Torque (Nm): 155
Dimensions
Overall length: 2415 mm
Overall width: 950 mm
Overall height: 1135 mm
Wheelbase: 1640 mm
Ground clearance: 130 mm
Weight (kg): 315
Seat height (mm): 658
Tank (L): 18.9
Tires
Front tire: 160/60 R18
Rear tire: 240/40 R18
Drivetrain
Final drive: Belt drive (toothed belt, no chain)
Ignition
Spark plug: NGK CR9EB
Fluids & Filters
Engine oil: SAE20W-50
Engine oil (with filter, L): 4.7
Oil filter: Hiflofiltro HF171
Air filter: Hiflofiltro HFA1903
Brake fluid: DOT 4
Fuel consumption
Estimated: 5.8 L/100 km
Estimated range: ~325 km on a full tank (18.9 L)
Note: real-world ±15-30% depending on riding style
Service
Battery: YTX20HL-BS
Service interval (km): 10000
Service interval (months): 12
Valve check (km): 24000
Parts and consumables for this motorcycle
Data is gathered with care, but without guarantee. Always confirm critical information with your dealer or workshop.
Service notes
Service interval: every 10,000 km or 12 months, whichever comes first. Valve clearance check every 24,000 km. Engine oil: oil grade SAE20W-50, 4.7 L with filter change. Spark plug: NGK CR9EB. Brake fluid: DOT 4. Tire size: front 160/60 R18, rear 240/40 R18. Always confirm critical values with the workshop manual or an authorised dealer.
OEM and quality aftermarket parts that fit this bike. Always confirm with your dealer before ordering.
Engine oil
Spec: SAE20W-50, 4.7 L (with filter)
- OEM OEM recommended engine oil (SAE 20W-50)
- Premium Motul 7100 4T (100% Synthetic, Ester)
- Premium Motul 5100 4T Technosynthese (Semi-Synthetic)
Which Motul for this bike?
| Motul 7100 4T ✓ | Motul 5100 4T | |
|---|---|---|
| Product | Motul 7100 4T — 100% fully synthetic | Motul 5100 4T — semi-synthetic |
| Best for | Sport, Naked, Adventure (600cc+), track | Standard, Cruiser, Scooter, daily use |
| RPM protection | Excellent — ester base, stable under load | Good — for normal riding conditions |
- Standard Repsol Moto Racing 4T (Synthetic)
- Standard Elf Moto 4 Tech (Semi-Synthetic)
Fully Synthetic vs Semi-Synthetic
| Fully Synthetic | Semi-Synthetic | |
|---|---|---|
| Base oil | 100% chemical synthesis (ester or PAO) | Mineral oil + synthetic additives |
| Heat resistance | Excellent — stable at extreme heat & RPM | Good — suitable for normal temperatures |
| Cold start | Better — reaches engine faster when cold | Good — adequate for normal climates |
| Change interval | Longer (up to 10,000 km) | Shorter (5,000–7,000 km typical) |
| Price | Higher | Lower |
Oil filter
Spec: Hiflofiltro HF171
- Premium Hiflofiltro HF171
- Premium K&N KN-171
Air filter
Spec: Hiflofiltro HFA1903
- Standard Hiflofiltro HFA1903
Spark plug
Spec: NGK CR9EB
- OEM NGK CR9EB
- Premium NGK CR9EIX
- Standard NGK CR9EB
Front brake pads
Spec: EBC FA400HH
- Premium EBC FA400HH
Rear brake pads
Spec: EBC FA400HH
- Premium EBC FA400HH
Front tire
Spec: 160/60 R18
- OEM OEM 160/60 R18
Rear tire
Spec: 240/40 R18
- OEM OEM 240/40 R18
Battery
- Premium Yuasa YTX20HL-BS
Brake fluid
Spec: DOT 4
- Standard TotalEnergies HBF4
Coolant
Service interval
Spec: 10 000 km / 12 months
- OEM Engine oil + oil filter change
- OEM Air filter inspection
- OEM Spark plug check
- OEM Brake fluid replacement: every 2 years
Valve check
Spec: 24 000 km
- OEM Hydraulic lifters — no manual adjustment needed
Suspension
Spec: 49 mm telescopic fork
- OEM Fork: 49 mm telescopic fork
Drive chain
