[Darren69]

Shorter exhaust tend to rob torque esp. from a v twin. Which is why Termi full systems have all those spaghetti manifolds to maintain and improve gas flow using negative pressure created by the other cylinder. And it works 10% more torque/power on an S4 with nothing more than the exhaust. You can feel the torque come onto the pipe in a similar way to 2 stroke expansion chambers.