idle fluctuation after slip-on

I just installed my arata slip-on on my 04 1000rr and now the bike wont stay at a steady idle it moves between 1k and 1200k rpm constantly. when i had stock the stock exhaust it idle'd steady at 1200k is there somthing wrong or is this normal with a slip-on. thanks.

yeah bro..mine had the same prob too..after i fix a yoshi GP Force slip-on, e idling needle won't stay still unless i had e bike run on the road for some time..had my PC III removed,dun noe if it will rectify dis prob..