Built around KTM's super motard motorcycle platform, the 2006 KTM 660 SMC pairs a 654 cc (39.9 cu in) liquid-cooled single cylinder, four-stroke architecture with road-focused gearing. In factory specification, peak output is rated at 28.2 HP (20.6 kW) at 6,250 rpm while maximum torque reaches 42.5 Nm (31.3 lb-ft) at 3,250 rpm, transferring power to the rear wheel through a 5-speed gearbox and chain final drive. With a specific output of 43.1 HP per liter and a 3,000 rpm working window between peak torque (3,250 rpm) and peak power (6,250 rpm), the engine character is prioritizing low-RPM tractability, mechanical longevity and relaxed throttle response over peak redline numbers.
On the scales, the 660 SMC measures 138 kg (304 lbs) dry, translating to a power-to-weight ratio of 0.2 HP/kg (4.89 kg per horsepower). Rider ergonomics and chassis geometry center around a 910 mm (35.8 in) seat height — reflecting a long-travel chassis stance that favors ground clearance and off-pavement control, combined with a 1,510 mm (59.4 in) wheelbase engineered for balanced agility and highway composure. The 9.2-liter (2.4 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Within MotoLibrary's KTM archive, this model family spans 4 indexed model years from 2003 to 2007, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
43.1 HP/L
Power-to-Weight
0.2 HP/kg (4.89 kg/HP)
Power Band Window
3,250–6,250 rpm
Standover Height
910 mm (35.8 in)
Engine
Displacement654.0 ccm (39.91 cubic inches)
Engine TypeSingle cylinder, four-stroke
Engine DetailsSingle cylinder, four-stroke
Power28.2 HP (20.6 kW)) @ 6250 RPM
Torque42.5 Nm (4.3 kgf-m or 31.3 ft.lbs) @ 3250 RPM
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.
