derestricting a suzuki katana

[Aerox_forever]

H E L P !!!!!!

My friend has a Suzuki katana brand new 53 plate, and it does 30mph maxed out. and its killing me going 30mph with him, so he looked into getting it derestricted and he said you can't.

So i rang up a suzuki dealer and they said you can't, so we took the bike apart and found a variator washer and a cone in the exhaust, so we removed them both and it only went 35mph pushing 40mph.

So i rang the suzuki dealer back and i said what we had done and he then said that it is restricted in the black box and the exhaust port, and i can't find a derestricted black box anywhere.
HELP!!! PLEASE!!!

 

[$aint]

As far as I know the CDI shouldn't be restricted.
What year is it?
How high does it rev?

 

[ChromeRoxRider]

I got a friend who has a Katana to.
He had a CDI restriction. The original exhaust sucks so I suggest your friend buys a new exhaust, doesn't have to be expensive and you'll see the katana will drive a whole lot better..

 

[Aerox_forever]

its a 2003 bike and it is restricted in the cdi and i was wondering if a cdi of anouther bike would work on his.

thanks anyway