well if like me you have a early cb400sf then you will have a standard stainless one piece exhaust where you cant put on an end can
my mod is as follows inside the exhaust are plates which stop the gas coing out in a straight line so i have got a big long drill just slightly smaller that the exit hole in the exhaust and put it in the end of the exhaust and drilled through the plate it now has a better sound and can breath more easily it not a race can but will sound and go a bit better with the mod and needs not rejetting

Hi there! Sounds like an interesting and easy mod. Did you have any MOT problems though? Also how long exactly do I have to drill?

Sound's like an idea to me, can you put a video up on YouTube so we An get an idea of what it sound like?
Cheers
Col