I am looking at adding a big bore kit to my Ultra Classic. I currently have SE super tuner, stage one air kit, HQ 525 cams and true dual with Vance & Hines slash down slip 2.5" slip on's.

I know the recommended is two into one for performance, however, I like the sound of my true dual and many bikes I hear with 2 into one just don't sound the way I want mine to sound.

So, my questions is what am I really giving up staying with the true dual vs. 2 into 1.

Thanks Guys & Gals

 

Last week I went from Rush Big Louie true dual exhaust to Drago's 2:1. Gain was 5hp/6tq. That being said, tq came on earlier and stayed a little longer....

Love the look and sound if the Drago's, but was probably not worth getting rid of my 2yr old true dual set up....

 

Thanks for the input. I'm not looking to drag race, but keep up with other out of the hole with wife on the back. Most the people I ride with are solo. I can always catch up but they take off a little faster and get around cars a little quicker. My bike is fine but you know how it goes, more is better. I figure the big bore added then the next thing would be heads and throttle body.

Thanks

 

My 10' RK has the Stage III 103" big bore and I have the Cobra true duals and it runs and sounds fantastic but I can't compare to a 2 into 1 as I have never tried it. If you prefer the duals then I would think 5hp/6tq wouldn't be enough to switch unless you are drag racing or something.

 

Should add that I have Revolution Performance 107, Stage II heads, T-Man 590 cams, PCV for tuner

 

What size big bore are you thinking? Will you be happy with it when you are done or will you go bigger later?

 

I agree with HD Rolling, how big you gonna go? Maybe different cams are in order? I don't think the pipes are going to make a huge difference if you are not going too big on cubes. When I had my 88 incher, the gear drive cams and a good tune did wonders, but I did have a 2 into1 V&H haha.

 

With your configuration I'd say that you're giving up a lot by not switching to a 2 into 1. I have been down the road trying to make my true duals more quiet and have found that after 5 different slip ons, they have a huge huge effect on power output. The absolute worst being V&H twin slash ovals and a close second Fatshotz. You'd pick up a ton with your small cammed 103 by going to a 2" baffle I would bet. Keep checking here or on eBay as they come up for sale all the time, those retarded twin slash ovals made me an extra $190 in my pocket when I sold them. The kid wanted to be the loudest on the block and he got it haha.

 

Definitely the 2.5" baffle is hurting a little on the bottom end..
When I wrecked my old SG with 103/255s .. I had 2" Rush.. there was a screw up and they put 2.5" on it. It was a dog taking off but would run decent on top.... the 2" had significantly more bottom end to the point it was "jumpy" when I would let off and hit it again, but still ran decent in mid to top.

With my new bike I went 2.25" Rush... when they dynoed it, the pipes blued.... they replaced them, but the ones that came in were 2"....... I could tell a difference over all on that one too... the 2s hit harder when I would first get on it, but since it was tuned for them, the 2.25 ran way better on the mid to top

Over all... the more sound/ bigger baffle, the less bottom end punch you will have.
I've never actually run a two into one.... I know they perform a little better... just don't like the sound at all... it's not worth a couple of hp/tq if you really like the sound of the duals...........
just a thought here.... go with a smaller baffle if they offer one for those pipes and try that first... it's a lot cheaper to play with... and if you don't like it somebody will probably want them...........
of course... if you are angling for a reason to get the big bore...... ignore what I have said LOL. Bigger is better.

 

It will avhe more torque and power with a 2 into. That is it plain and simple. Building a a motor and running true duals is almost self defeating assuming you are building the motor to get more power. Specifics on how much tq and power vary greatly depending on your build, tuner, exhaust etc etc.

Would I build my motor and put true duals? Nope. Has it been done by me in the past? Yes. Some companies make a ghost pipe to go with the 2 into 1 if you are looking to keep that balanced look of duals with the benefits of a 2 into 1. The first two that come to mind are D&D and Thunderheader. I think Drago's makes a ghost pipe as well.