I have a stock 2011 SG with Rush slip on's. I have toyed with the exhaust a bit, to see what it sounds like. Granted I still have the cat but with the wrapping off the Rush baffles it sounds better, I was wandering what would happen with the entire baffle out? It still has stock AC and not SEstage1...with the cat will it hurt the bike without a baffle? I need to de cat but haven't yet. Any ideas, pros-cons?

Thanks
Tim

 

dont think it will make a lot of difference as long as the cat and a/c are there. probably gonna start running real lean when you get a high flow ac and remove the cat.

 

the cat itself is a restriction to flow and that also affects the sound.
the stock a/c is also quite restrictive.

You should be just fine - mechanically- until you change the ability of your motor to flow more air in and out.


but fiddling with your mufflers is not going to do much with the cat in place.


as you proceed, keep in mind that "drag pipes" ( straight pipes with no restrictions/mufflers)- are about as loud as you get, and produce great power at 6000 rpm--- but develop less power at 3000 rpm.
So louder can be "slower" if you do much riding near 2500~3500 rpm.

pipe length, diameter, muffler, restriction, crossover design ( if any) all affect at which rpms range the motor make increased power ( over stock) and where it may make less.

Once you are ready to increase your power, all this will come into play.

( and if cost is your hold up, the ness big sucker can be found for $115 on ebay, the cat is a DIY, perhaps involving a local welding or muffler shop, and mufflers you have- just about any mufflers will work with the cat gone. Tuning: Nightrider.com XIEDS work for me at $125)

other pipe considerations;
loud bikes tend not to be popular with neighbors, often are relegated to the rear of a group of riders. and a not much fun if you are riding 8 or 10 hour days...noise becomes fatiguing and it's kinda nice to listen to the stereo once in a while.

Mike

 

I had the Rush baffles on my bike from the stealership. I would bet if you gutted the cat, and did the 2.5" baffles (unrapped) you would like the sound of it. It's not straight pipes, but has a good HD tone.

 

I was wandering what would happen with the entire baffle out? It will be louder.
With the cat will it hurt the bike without a baffle? Hurt what?
the cat itself is a restriction to flow- This is absolutely false.
The cat traps heat and muffles sound but it is not a flow restriction.

 

OK, I'm not a mechanic, but I've seen pictures of the cats on this forum taken by people who were showing step by step pics on how they did theirs. I guess my question is, how can they NOT be restrictive? It looks like a dense packing of honeycombed metal. It just seems to me anytime you cram anything into a head pipe like that, it cant help but restrict flow.....This isnt me being a smartass, now just really curious

 

Excellent info guys, I have taken out the baffles, yes it is louder and to my supprise not too shabby. Still has the low rumble and good HD tone. Until I get the head pipes either gutted or replaced I may just put the baffles back in without any padding and see if it changes again. Who knows. I will try to post some sound clips. I have several before and afters.
Thank again
Tim

 

The catalyst chamber has a way larger cross section area than the two primaries combined, but the catalyst cross section open area of the mesh, is equal to the cross section area of both primaries combined. It's an illusion, seems like it just must be a restriction, but it is not. Now if you had a chamber that was the same cross section area as the two primaries combined, and it was filled with the same basic catalyst mesh, then you would have a restriction. Honeycomb is not really a good descriptive for this material, the catalyst is more like an enlongated mesh, like a bunch of tiny straight through ports. There have been some flow test results published but I can't remember who or where.

 

I removed the cat and put the stock pipes back on and it opened it up enough to where it sounds like I put slip-ons on it. When you get it on the road and put throttle to it youve got more throat seriously. Do the cat first before doing anything to the baffles then see if you want more. I put a strong flashlight inside the stock pipe before I remounted it and you can see light from the back side. I don't think theres a whole lot of baffles in there, I believe the cat did most of the restricting which once you undertake the job of removing it your going to be amazed at what those two pistons have to push exhaust threw.....kinda rediculous if you ask me.

 

TUCCI is "in the know"...amen brother, you and I know!

Non- restricted flow.....BS!