exup rattle

[breamcatcher]

Hi everyone, got my bike back saturday repairs look good, they fitted the exup valve that i got with the set of r1 downpipes off a 2001 which have never been used  works great but there is a small rattle they are saying that the machined bush in the collector box has wear in it and i will need a set of new pipes is this right or is there something i can do. cheers Breamcatcher