Fitted one of these now to my X, very pleased with the look but a total & utter ****** to fit. It took me one night to realise that the second heder pipe was too long and would not align and upon advice from Metal Mule I cut 5mm off the end of the tube. The can is such a tight fit that I had to trim off some material from the rear mudguard/light unit (there is only about 2mm clearance) and getting the whole thing to line up on your own is a bit difficult as you cannot fit the front pipe and then the can as there is not room to do this. End result 8.5Kgs lighter sounds like a proper single and has got rid of all that plumbing unnder the engine. Can't say I notice any difference in powver or weight but I think it looks great.