Would a system like the Quat-D not lose bottom end torque/ horsepower being little more than 2 headpipes and a silencer box? I would have thought that being a big twin, the length of standard type system would be more efficient, specially if a full flowcollector box is utilised to allow gas expansion through both cans. Iquite like the look of the Quat-D, but no way would I buy a "performance part" that makes my bike slower. Fully admit that I have no proof of any losses in power of these pipes, just previous experience of building and tuning engines, thought I'd add my Incidentally,if you're in Belfast, I'm only down the road in Drogheda, might run into you at the Ulster GP or somesuch? All the best J