I have had several exhausts on my Fatboy over the years - BSS, Big Radius 2-1, Bassani ProStreets, Fatcat, and now Road Rage 2-1 with short meg. I know all bikes are different in how they respond to exhausts, and mine just seemed to work best with the Big Radius 2-1. Since switching to 2-1 pipes with stepped headers, my torque curve move to the right on my dyno sheets and I am not real happy with the low end snap I used to have when rolling I the throttle at 65 - 70 mph.

I have had bike tuned by reputable tuner each time, but I still have a real bad dip between 2000 - 3250 rpm then torque kicks and bike rips hard up to redline.

I have been thinking of switching to a non-stepped header - maybe Thunderheader or LSR. I love the TH sound and like that baffle can be modified to improve low end torque dip. I know RB claims their B style LSR creates moe torque with the longer rear primary that wraps up in front of cam chest. Is this true of the TH pipes also. I see they don't offer that style TH for FLST bikes, but I have forward controls so I assume I can make another softail model fit. Any help whether the TH with longer rear primary creates more low end power and if it will fit a flst Fatboy is appreciated.

As much as I have read up on exhausts when buying in the past, you would think it would get easier, but every thread just confuses me more. For every post saying this pipe works well on a 95" engine, blah, blah, there is another saying the pipe sucks.

 

FYI - I got rid of ProStreets because I could never get headers to bolt on tight - they would loosen and I would get popping after 40 miles of riding, plus low end felt soft. Fatcats were not on bike long as I had a run-in with truck and pipes got trashed. I did have these tuned, but not by my regular tuner and I don't think they ever got dialed in all the way. I just never cared for the sound of the fatcat when I was on bike. Bike sounded good when I had a friend ride it, but it sounded like a buzzing in my ears when I was riding. I was actually taking the bike to retune with the Fatcats the day I got hit by truck, so never got a good feel for what those pipes might have done with a good tune.

 

From the dyno tests I have seen the Thunderheader does not make good low end power. They are also known to rust. Have you considered a Supertrapp?

 

My father-in-law has a thunderheader on his 95" and that thing has solid performance throughout the throttle. I run thunder header on both my night train and shark nose. The glide has the race pipe. Best exhaust I've ever ran. On the train (96"). I started with the VH short shots, and changed to the supertrapp. The supertrapp was awesome for its "tunability" but the sound was TERRIBLE! Made a "plat" sound. Even my wife made fun of me with that exhaust on lol.. Changed to the thunderheader played with the baffles (myself without dyno) and I love the performance and sound. But to each their own...

 

I like my d and d bobcat. Not annoying to me while I ride but sounds healthy. Quality piece, performs well. The rb pipe was neck and neck for me but I didn't want to wait that long. no regrets here.

 

I have considered supertrapp in past - every tuner I talk to had good things to say, but not crazy about the sound. I have seen some TH's in bad shape, but I don't think the owners ever cleaned them. The bassani's I've had were not near the chrome quality of the V&H or Fatcats, but wiping them down regularly helps. I really like the look of the LSR pipes, but never see any dyno sheets to see what the torque curve looks like.

 

Anybody else see their torque curve shift to the right when going to stepped headers?

 

i went from the BSS to a supertrapp. i hated the supertrapp because it was too quiet, i since pulled baffle and cut 6" off of that 18" beast and tossed the stuffing. definately a noticible difference in tone. i also just grabbed my dyno sheet after i had jason at Faribault harley tune and dyno this spring. that guy is a guru on a dyno and i have NO dip in tq or hp after his tune, where as the previous dyno had the same dip about 2800-3500 but pulled like hell above that

 

I've run TH's on my bikes for a long time and never had them rust. (never heard them as "known to rust" either for what that's worth) They make good power across the range, sound great, aren't insanely expensive like some pipes nowadays can get and they look damn good.

I've ran a ST on an older XR and it was a great pipe - but I can't imagine having that sound chase me down the highway all day on a run.

 

what cams you running... just wondering because you mentioned the dip between 2-3k.

Some cams like some pipes better than others..