On a V-twin with separate exhaust systems, the two cylinders do not operate evenly. Each cylinder generates pressure waves that propagate through the exhaust. A crossover connects both exhaust headers, allowing these pressure waves to support each other.
The main advantages are:
More torque in the low and mid-range RPM band: Thanks to improved use of the pressure waves, the cylinders are scavenged more effectively. This often makes the engine more responsive and flexible.
Smoother engine operation: The pressure pulses balance each other out to some extent, resulting in a smoother-running engine.
Slightly more peak power: Usually only around 1–3%, provided the rest of the exhaust system is also tuned accordingly.
Reduced heat buildup: Depending on the design, the exhaust gas flow is distributed more efficiently.
Changed exhaust note: A matter of personal preference. Sound often becomes fuller and deeper, though sometimes slightly less "harsh."
Lower fuel consumption – an expected reduction of about 1 L/100 km.
