Re: Re: B1 Project Started. Home › Forums › All Things 750 Twin › Projects and Progress › New Projects › B1 Project Started. › Re: Re: B1 Project Started. 27th February 2013 at 12:27 pm #8735 TangoParticipant Also I have managed to fit the K&N filters to the back of the carbs. Not sure if I’m going to run the bike like this yet? Or put the air box back on? Anybody got any thoughts on that? Are K&N’s Ok on these bikes or am I better of with the standard set up?