I had this problem this summer.
When you'll read how I fixed it, you'll laugh.
The killswitch box isn't completely waterproof. Your bike is a 2005, it has seen a lot of roads and different weather (rain,shine, etc.) and there's probably a lot of junk inside. Open it, clean it (especially the connections), close it, try it.
Worked for me
Current bikes: YZF-R6 & Z1000
MJS shorty slip-on, K&N filter
/ Shortened oem slip-on, K&N filter and PC3, rizoma levers
Old bike : FZ1 03
Originally Posted by Aj-Agwa
why when i put the straight pipe on a i rev it to like 5 or greater RPM the bike turns off??