Hey Guys n dolls, I need some technical advice. I've always had Vance n Hine exhausts on all my Harley's, really love them. Problem is the Cops in Australia hate V & H and always bust us for noise. So, I've switched over to Screaming Eagle which "somehow" Aussie cops don't seem to focus on. My Screaming Eagle Street Cannons are great on the Road King (great sound) BUT the Screaming Eagle Street Cannons on my 48 Sportster, sound pretty feeble. I'm told that if I pull out the baffles, cut off an inch or two, pop baffles back, they will sound a whole lot better. MY QUESTION..... will that mod have a negative effect on performance? Would appreciate any comments from you people who work on bikes and know about this stuff... tkx Pat

 

Not sure if baffles are required in Australia (they are in my state), but IMO the SEs would probably sound and perform better with Thunder Torque Inserts and no baffles. Check out DK Customs site. They have some videos of various exhaust with and without baffles and with and without TTIs. But TTIs with no baffles will probably too loud for your liking and the cops. You could perhaps install TTIs with your baffles in too deepen the sound and reduce reversion.

 

Cycle Shack makes a performance baffle that replaces the Screamin Eagle baffle and sounds and runs a lot better

 

Hey, thanks for the replies, very appreciated!!! Still, what I really want to establish is what negative effect (if any) will there be on the performance of the bike IF I cut down & shorten the current baffles. Would appreciate any other technical advice re that specific plan..... if all else fails, I'll take the advice about Cycle Shack performance baffles.... thanks Pat

 

Thanks man, really do appreciate the advice. Still, the question I still need an answer too is......what negative effect (if any) will there be, if I cut down n shorten the existing baffles?


If I cant do that, I'll take the advice about Cycle Schack Performance baffles... cheers pat

 

I think I can help here. If I am breaking any rules by linking this please let me know. I am not advocating tti's by showing this I just think this video can demonstrate. From my understanding growing up, the more free flowing an exhaust is the better the power often is. Straight pipes with no baffles however will rob your lowend. Baffles help to create some back pressure and reduce sound. These little lollipops basically create some back pressure.
Therefore back to your question there is really no way to know for certain anything except more than likely some back pressure will be removes as the baffles tend to create it (I believe by creating a vortex from the cheese grater shaped dimples) ie the less of these dimples the more sound and the less back pressure. However simply removing half of these dimples may not make you anymore power as a better baffle with better design would all around be better. Mind you This all makes sense in my head but with my head this far up my a&& you can guess where I'm speaking from.
Personally I took out my baffles and added tti's.

Edit: growing up I was always taught that you want some back pressure as none can hurt your valves, cause a rough idle (which isnt really a secret) and robs your low end.

 

HI all, thanks for the hints... cheers Pat

 

By cutting down the pipes and shortening the existing baffles, two things will occur-

1. The exhaust will be louder

2. You will have more top end power, and a drop in low and mid range power.

You can gain all of the drop in low and mid range power, PLUS more back by installing some Thunder Torque Inserts. They will also deepen the tone just a bit.

With respect to sawka, the myth about needing back-pressure is strong. I grew up with it also.

What an engine needs to not lose low & mid range power is the absence of reversion. The common method for reducing reversion is a baffle. Baffles create back-pressure. Back-pressure is like putting the brakes on the engine...but since it reduces reversion it sort of equals out (if it is not over or under baffled), and definitely gives the illusion that back-pressure is needed.

Thunder Torque Inserts operate on a totally different (patented) principle, they stop reversion while creating very little back-pressure. Net result is that you get the best of both worlds instead of a compromise.

The TTI's provide benefit to any exhaust that is un-baffled OR running an open style baffle, like V&H, Street Cannons, Cycle Shacks, and virtually every other after-market slip-on.

Here's a vid of some bikes running TTI's, some baffled, some un-baffled.

 

thanks a heap for that technical advice team DK, very appreciated and I now need to buy your TTI's but need some advice about best ones for my bike.
I have a 2015 / 1200 Sportster 48 with Screaming Eagle pipes. I intend to leave the baffles in and want essentially a better (louder) sound. Improvement in any performance will be a bonus.


So, what item do I need to order ? best regards Pat

 

Hi Pat,

There are several configuration choices to the Street Cannons. Which configuration your run will depend on what size TTI you need.

You can either post some pics of your pipes here (along with measurements, you can email them to my attention at Support@DKCustomProducts.com

Below is a picture of a Street Cannon for a Sportster (no end cap). You can see the catalytic converter at the end of the pipe.




Also in your email, or post, let me know how much of the baffle you are wanting to cut off.