MotoSpecs

2017 Harley-Davidson Dyna Fat Bob vs 2018 Triumph Bonneville Speedmaster

Full specifications comparison • 2 motorcycles

Comparing 2 motorcycles
2017 Harley-Davidson Dyna Fat Bob 2017 Harley-Davidson Dyna Fat Bob

Custom / cruiser

Engine
Four stroke, V-Twin, Twin Cam 103° with integrated oil cooler
Power
N/A
Top Speed
N/A
Weight
321 kg / 708 lbs
2018 Triumph Bonneville Speedmaster 2018 Triumph Bonneville Speedmaster

Custom / cruiser

Engine
Four stoke, parallel twin, 270o crank, SOHC
Power
57.4 kW / 77 hp @ 6550 rpm
Top Speed
N/A
Weight
245.5kg / 540 lbs
Full Specifications
General
Year2016 - 172018
Make ModelHarley Davidson Dyna Fat BobTriumph Bonneville Speedmaster
Dimensions
Seat HeightUnladen 690 mm / 27.2 in705 mm / 27.7 in
Wheelbase1620 mm / 63.8 in.-
Ground Clearance125 mm / 4.9 in-
Length2400 mm / 94.5 in-
Weights & Capacities
Dry Weight306 kg / 675 lbs245.5kg / 540 lbs
Fuel Capacity18 9 Litres / 5.0 US gal12 Litres / 3.17 US gal
Maximum Load / GVWR492 kg / 1085 lbs-
Oil Capacity2.8 Litres / 3.0 US qt-
Wet Weight321 kg / 708 lbs-
Performance
Max Power-57.4 kW / 77 hp @ 6550 rpm
Max Torque132 Nm / 13.5 kgf-m / 98.0 ft/ lbs @ 3250 rpm106 Nm / 10.7 kgf-m / 77.4 lb-ft @ 3100 rpm
Engine
Displacement1690 cc / 103 cu. in1198 cc / 73.1 cu in
Engine DetailFour stroke, V-Twin, Twin Cam 103° with integrated oil coolerFour stoke, parallel twin, 270o crank, SOHC
Bore x Stroke98.4 x 111.1 mm97.6 x 80 mm
Compression Ratio9.6:110.0:1
Cooling SystemAir cooledLiquid cooled
ExhaustChrome, "Tommy Gun" 2-1-2 collector exhaust with dual mufflersStraight line stainless steel twin-skin slash cut twin stubby silencers
Fuel Consumption5.6 L/100 km / 17.9 km/l / 42 US mpg-
Fuel InductionElectronic Sequential Port Fuel Injection (ESPFI)Multipoint sequential electronic fuel injection
IgnitionSingle-fire, non-wasted, map-controlled spark ignitionDigital
Lubrication-Wet sump
StarterElectric-
Drivetrain
ClutchMulti-plate, wetWet, multi-plate
Final DriveBeltChain, X-ring
Gear Ratios1st 9.311 / 2nd 6.454 / 3rd 4.793 / 4th 3.882 / 5th 3.307 / 6th 2.790:1-
Primary DriveChain, 34/46-
Transmission / Drive6 Speed 6-Speed
Chassis
Frame TypeMild steel, tubular frame; rectangular section backbone; stamped, cast and forged junctions, forged fender supports; MIG weldedDual tubular steel cradle
Suspension - Front49 mm with polished aluminum fork triple clamp and dual-rate springs,41 mm Kayaba fork
Suspension - RearCoil over shockKayaba twin shocks with adjustable preload
Lean Angle31°-
Rake29°-
Trail125 mm / 4.9 in-
Wheel Travel - Front127 mm / 4.9 in90 mm / 3.5 in
Wheel Travel - Rear54 mm / 2.1 in73 mm / 2.8 in
Wheels & Brakes
Brakes - FrontSingle 300mm disc, 4 piston fixed caliper2 x 310 mm Disc, 2 piston calipers, ABS
Brakes - RearSingle 292mm disc, 2 piston torque-free floating caliperSingle 255 mm disc, 2 piston caliper, ABS
Tyres - Front130/90B16 67130/90-16
Tyres - Rear180/70B16 77H150/80-16
WheelsGloss black cast aluminum wheel with laser etched graphicsWire 32-spoke, steel rims

Verdict

Winner on specs

2017 Harley-Davidson Dyna Fat Bob

The 2017 Harley-Davidson Dyna Fat Bob edges out the 2018 Triumph Bonneville Speedmaster thanks to its higher torque, larger fuel tank, higher front wheel travel and larger displacement. Specifications are one part of the picture - dealer support, parts availability, and intended use all matter too.

Key Differences

2017 Harley-Davidson Dyna Fat Bob - Advantages

  • Higher torque: 132 Nm vs 106 Nm - more pulling power across the rev range.
  • Larger fuel tank: More range between stops - an advantage on touring routes and remote roads.
  • Larger displacement: 1690 cc vs 1198 cc - more cubic capacity means broader torque delivery and greater low-end pull.
  • More front wheel travel: 127 mm vs 90 mm - greater compliance over rough surfaces.

2018 Triumph Bonneville Speedmaster - Advantages

  • Liquid cooling: Consistent engine temperature in stop-start traffic and hot climates.
  • Dual front discs: Greater stopping power and better heat management under hard braking.
  • More rear wheel travel: 73 mm vs 54 mm - absorbs bigger hits and rough terrain better.

2017 Harley-Davidson Dyna Fat Bob vs 2018 Triumph Bonneville Speedmaster - FAQs

What are the engine differences between the 2017 Harley-Davidson Dyna Fat Bob and 2018 Triumph Bonneville Speedmaster?
The 2017 Harley-Davidson Dyna Fat Bob uses Four stroke, V-Twin, Twin Cam 103° with integrated oil cooler, while the 2018 Triumph Bonneville Speedmaster is powered by Four stoke, parallel twin, 270o crank, SOHC.
Which bike is better for shorter riders, the 2017 Harley-Davidson Dyna Fat Bob or the 2018 Triumph Bonneville Speedmaster?
The 2017 Harley-Davidson Dyna Fat Bob has the lower seat at Unladen 690 mm, making it more accessible. The 2018 Triumph Bonneville Speedmaster sits higher at 705 mm. A seat height below 800 mm suits most riders; above 820 mm shorter riders may need to tiptoe.
Which has the larger fuel tank, the 2017 Harley-Davidson Dyna Fat Bob or the 2018 Triumph Bonneville Speedmaster?
The 2017 Harley-Davidson Dyna Fat Bob has the larger tank at approximately 18 litres vs 12 litres for the 2018 Triumph Bonneville Speedmaster. At 5-6 l/100 km that is roughly 300-360 km vs 200-240 km between stops.
Which should I buy, the 2017 Harley-Davidson Dyna Fat Bob or the 2018 Triumph Bonneville Speedmaster?
Both are strong choices. The 2017 Harley-Davidson Dyna Fat Bob has the edge in higher torque and larger fuel tank, while the 2018 Triumph Bonneville Speedmaster stands out for liquid cooling and dual front discs. Visit dealers, arrange test rides, and factor in local parts and service costs - these often matter as much as the spec sheet.

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