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• 72-degree cylinder angle and a very compact crank case and cylinder head design allow the engine to be located far forward in the chassis, distributing 54 percent of the vehicle weight to the front tire.
• The 72-degree V-angle provides a straight path for the down-draft intake system.
• A cylinder angle of 72 degrees was chosen because it provides the right balance between compactness and reducing vibration. The engine is also fitted with three balance shafts: two balancers for canceling primary rotating imbalance and a third balancer for canceling the rocking couple.
• The displacement of 1125cc was chosen to create an optimal 103.0mm bore x 67.5mm stroke configuration – generous bore for more valve area and better breathing and short stroke for reduced friction, increased rpm range and instant throttle response.
• The engine has a low-inertia flywheel for a quick-revving performance and smooth shifting.
• The engine is a stressed member of the frame and contributes to overall chassis rigidity. The swingarm pivot is located in the engine cases.
• Each cylinder features twin overhead cams with a self-adjusting chain drive to the intake cam and gear drive from the intake to the exhaust cam. This design requires less space over the cylinder head than a two-sprocket design, allows the engine to be located further forward, and reduces engine weight.
• Valves are actuated with light weight finger followers and adjusted with shims, a design derived from Formula 1 engine technology.
• Finger follower valve actuation reduces friction, permits a quicker valve opening, and eliminates valve float. This design also allows a steep valve angle of 18 degrees which aids the downdraft fuel injection system. The design of the follower retention system makes shim replacement quick and easy, reducing maintenance costs. Valve covers are magnesium to reduce weight.
• Primary balancing with three internal shafts reduces chassis weight by minimising vibration isolation requirements.
• Dry sump oiling reduces internal windage losses. An integrated oil reservoir is located in the lower left side of the crankcase casting to lower the centre of gravity and help keep the engine compact.
• Buell® DDFI3 Electronic Fuel Injection is a closed-loop system for precise mixture control, resulting in smoother throttle operation and better fuel economy. Dual downdraft 61mm throttle bodies provide superior intake air flow.
• Ram-air system pressurises the air box for a peak performance gain of up to 5 percent. The air intake is located between the front fork legs and below the fairing. Air flow to this area and the size and shape of the intake were optimised using computational fluid dynamics (CFD) models. The 12-litre airbox is designed to accommodate a large air filter and to be easy to service.
• Twin side mounted free flowing radiators are mounted longitudinally within aerodynamic cowlings. The position of the radiator system lowers the centre of gravity and centralises mass, and allows the cowlings to direct free-flowing air to each radiator. The cowlings have an internal vane (splitter) to split airflow efficiently and were designed with computational fluid dynamics (CFD) models to optimise air flow at all speeds and to create a pressure differential around the radiator to pull air through the core. Hot air is also exhausted away from the rider for enhanced comfort.
• The exhaust system features a large-volume muffler mounted below the engine to optimise cg location and mass centralisation. The muffler is tuned to produce a linear horsepower and torque curve without the added cost, weight and complexity of an active exhaust system. A Helmholtz chamber within the muffler further reduces noise output. Twin brushed stainless exhaust outlets produce less exhaust noise than a single side mounted outlet.
  

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