Built around Ducati's naked motorcycle platform, the 2019 Ducati Monster 821 Stealth relies on a 821 cc (50.1 cu in) air-cooled v2, four-stroke powerplant. In factory specification, peak output is rated at 109 HP (79.6 kW) at 9,250 rpm while maximum torque reaches 86 Nm (63.4 lb-ft) at 7,750 rpm, transferring power to the rear wheel through a 6-speed gearbox and chain final drive. With a specific output of 132.8 HP per liter and a 1,500 rpm working window between peak torque (7,750 rpm) and peak power (9,250 rpm), the engine character is reflecting a performance-oriented street tune that balances strong mid-range pull with an energetic top-end rush.
On the scales, the Monster 821 Stealth measures 205 kg (452 lbs) wet (curb), translating to a power-to-weight ratio of 0.53 HP/kg (1.88 kg per horsepower). Rider ergonomics and chassis geometry center around a 785 mm (30.9 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance, combined with a 1,480 mm (58.3 in) wheelbase engineered for balanced agility and highway composure. The 16.5-liter (4.4 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Within MotoLibrary's Ducati archive, this model family spans 2 indexed model years from 2019 to 2020, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
132.8 HP/L
Power-to-Weight
0.53 HP/kg (1.88 kg/HP)
Power Band Window
7,750–9,250 rpm
Standover Height
785 mm (30.9 in)
Engine
Displacement821.0 ccm (50.10 cubic inches)
Engine TypeV2, four-stroke
Engine DetailsTestastretta 11° L-Twin
Power109.0 HP (79.6 kW)) @ 9250 RPM
Torque86.0 Nm (8.8 kgf-m or 63.4 ft.lbs) @ 7750 RPM
Compression12.8:1
Bore x Stroke88.0 x 67.5 mm (3.5 x 2.7 inches)
Valves/Cylinder4
Fuel SystemInjection. 53mm throttle bodies with full Ride by Wire
Fuel ControlDesmodromic valve control
CoolingAir
Transmission
Gearbox6-speed
Final DriveChain (final drive)
ClutchAPTC slipper and self-servo wet multiplate clutch with control cable
Performance
Emission DetailsEuro 4
ExhaustStainless steel muffler and aluminium and cap; lightweight 2-1 system with catalytic converter with 2 lambda probes
Chassis
Frame TypeTubular steel Trellis frame attached to the cylinders head
Rake24.3°
Trail93 mm (3.7 inches)
Front Suspension43mm upside-down forks
Front Travel130 mm (5.1 inches)
Rear SuspensionProgressive linkage with adjustable monoshock. Aluminium double-sided swingarm
Rear Travel140 mm (5.5 inches)
Wheelbase1480 mm (58.3 inches)
Wheels & Brakes
Front Tyre120/70-ZR17
Rear Tyre180/55-ZR17
Front BrakesDouble disc. Semi-floating discs, radially mounted Monobloc Brembo M4-32 callipers, 4-pistons, axiial pump with ABS as standard
Front Brake Ø320 mm (12.6 inches)
Rear BrakesSingle disc. 2-piston floating calliper with ABS as standard equipment
Rear Brake Ø245 mm (9.6 inches)
Wheels10-spoke in light alloy. Pirelli Diablo Rosso II tyres.
Dimensions & Weight
Dry Weight180.5 kg (397.9 pounds)
Weight incl.205.0 kg (451.9 pounds)
Power/Weight0.6039 HP/kg
Seat Height785 mm (30.9 inches) If adjustable, lowest setting.
Alt. Seat Height810 mm (31.9 inches) If adjustable, highest setting.
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Power
Compare engine output with similar motorcycles if acceleration, highway use or two-up riding matters.
Torque
Torque is useful for judging real-world pull, especially for touring, commuting and loaded riding.
Seat Height
Check the seat height against your inseam and riding posture before choosing a motorcycle.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
