flapper mod and/or laser exhaust

okay, just about to order laser exhaust for my 06 1krr, but i have a few questions. everyone talks about a flapper mod, this is something that i am not at all familiar with?????

second question, i've seen some complaints on the laser exhaust that you need the power commander or it makes the bike run rough, and that you wind up with some loose cables???

done alot of tinkering on bikes but need some advice before i spend the money, thridly i'm having a hard time even finding someone locally to get the laser pipes from, where is everyone getting there's from?

question one search for pair snd flapper mod

question 2 the loose cables are from the servo motor. i just taped mine up where they do not flap around. I am not familiar with the laser but i just put an rs-5 on my 06 1k and it runs pretty nice.