i am sure others will jump in with advice, but my first thought on the roadhouse's is are they "true duals?" a ridin buddy has a HD ultra-classic dresser, and he had his "y" pipe welded closed from the front cylinder on his pipes in order to obtain "true duals"

he had a cam installed and got porting or something done, but he was told his pipes needed to be "true dual" meaning each cylinder exhausted thru one pipe each for balance. it has something to do with performance.

i was told that if you go to a certain extent with performance mods, your pipes should be true duals and also be same in length; the staggered pipes. i aint plannin on reaching that extent, so my cobra speedsters are fine!

maybe some of the other more experienced guys can elaborate!