will a 04 kfx kawsaki slip on work with no trouble on a 07 z400? It looks like a team suzuki yoshimura pipe.
SUZUKI QUADSPORT EXHAUST LTZ 400 SLIP ON YOSHIMURA ATV:eBay Motors (item 110393523493 end time Aug-20-09 08:25:30 PDT)

 

Actually when they changed the cams in 2005, the cannister stayed the same stock.....But the aftermarket companies generally list a different muffler/cannister for the 2005 and up models so you might not want to take a chance....... It will probably mount up and everything but there might be a difference in cannister length or path......

To be sure I'd call up Yoshimura and ask them.