I have a 2012 Speed Triple R fitted with an Arrow Lowboy slip-on. It's not a full system, as far as I can tell, as the header has cast pieces, there are no joining springs and the original heat shield bracket is on there next to what looks like a Cat - in short it doesn't look like an Arrow race header. The bike came with tune 20607 installed, which is for the Arrow Lowboy full system. I'm thinking the 20604 tune, which is for the Arrow slip-on, would be more correct, although I've not looked at the difference between the two. Thoughts anyone please?