Guys help please I did the SE 103 stage 4 on 09 SG, used the stock head pipe and the CFR mufflers, they sound awesome but run like crap at idle to 1500rpm, dyno shows dip in curve at like 1850 as well, Dealer tried everything to get rid of off idle stumble and such, tried stock Throttle body, tried putting 02s out of dyno write into head than tunning each cylinder, tried smart tune etc, I have 20 hrs on dyno and still off idle stumble and poor low end till she revs up, after all this dealer put on my old V@H monster oval and it was like a new bike idle was clean, no stumble power curve was clean no dip, etc, I was in shock, Bike made 110 hp and 105tq, the CFRs sound awesome but they have zero in back pressure and it was untuneable, Does anyone else use these mufflers and what did you find, I googled it and it seems alot of guys are complaing that they stmble off idle, Cary Faas told me to send them back for a cone to be installed, he also gave me the sales pitch that he has hundreds of these out there and they all work fine, that is BS almost all that i read is same issue, I also want to be fair, if the bike is stock or small build they seem to be less affected, but we tried everything and no good, help please share ypur thoughts here I want to use them they sound bad *** but man i can not live with the stumble and bumble Brett