The XSR has a complete, all in one system (the silencer is welded to the header pipes). So the standard silencer isn't removable in order to fit an aftermarket can.
However, there are one or two slip-ons available for the MT07 that will also fit the XSR. Be prepared to get a hacksaw out to cut apart your standard exhaust! These slip-ons use the original header pipes. Obviously once you've taken a saw to your standard system there's no going back, unless you know someone who's handy with a Tig welder.
The only ones I know of are M4, Werkes.
