Baffled or Not?

[BIG--T]

I have a Standard with Cobras 6-6. I know there has to be some back pressure, but if running without baffles do I lose a significate amount of power or is it the opposite?

[Tropic traveler]

You lose power WITH the baffles in. You lose LOTS MORE power with the baffles out.
The normal flat spot on the Valks torque curve becomes much bigger with Cobras.

But boy do they sound nice!

[SCain]

Take out the baffles and take it out for a spin and report back. 

[BIG--T]

Take out the baffles and take it out for a spin and report back. 

That's the very first thing I did when I bought her a month ago. In retospect I should have road it a while before. I guess I'll put them back in tomorrow. I do love that sound and scare HD riders!

[Bobbo]

I have a Standard with Cobras 6-6. I know there has to be some back pressure, but if running without baffles do I lose a significate amount of power or is it the opposite?

Back pressure isn't what increases power or efficiency, it's scavenging.  The exhaust is pulsing and contracting as it cools, and the baffles break up the pressure waves to help increase scavenging.

[Tropic traveler]

If you haven't ridden your Valk with a stock or close to stock exhaust on it it will be hard to judge {using the reliable butt dyno  } what you've lost or gained. IMO the ROAR of open exhaust gives you the feel of more power while acually losing power. Explains a lot of the V-twin racket anyways!  
I'm sure there are members that have some real proof of the power loss that Cobras or any other open pipe set up by way of dyno runs.
All my observations are based on our Valks. My '97 has a quiet near stock back pressure glass pack with added baffleing to stop droning & it will flat outrun the other 2 Cobra equipped Valks hands down.
Also when we got Kim's Valk it had stock exhaust. It came with an extra set of Cobras & Kim wanted the noise so on went the 6x6's. I noticed a power loss right away.
When I bought the '99 it had unbaffled Cobras but a set of baffles came with it. I also noticed a slight power increase {& a big headache decrease} after installing the baffles.

[Tropic traveler]

I have a Standard with Cobras 6-6. I know there has to be some back pressure, but if running without baffles do I lose a significate amount of power or is it the opposite?

Back pressure isn't what increases power or efficiency, it's scavenging.  The exhaust is pulsing and contracting as it cools, and the baffles break up the pressure waves to help increase scavenging.

That is true. I think the reason why my glasspack set up works so well for me is it turned the exhaust into two 3 into 1 systems with just enough back pressure to work well. A 3 into 1 has a good scavenging effect compared to 3 singles a side.

[BIG--T]

If you haven't ridden your Valk with a stock or close to stock exhaust on it it will be hard to judge {using the reliable butt dyno  } what you've lost or gained. IMO the ROAR of open exhaust gives you the feel of more power while acually losing power. Explains a lot of the V-twin racket anyways!  
I'm sure there are members that have some real proof of the power loss that Cobras or any other open pipe set up by way of dyno runs.
All my observations are based on our Valks. My '97 has a quiet near stock back pressure glass pack with added baffleing to stop droning & it will flat outrun the other 2 Cobra equipped Valks hands down.
Also when we got Kim's Valk it had stock exhaust. It came with an extra set of Cobras & Kim wanted the noise so on went the 6x6's. I noticed a power loss right away.
When I bought the '99 it had unbaffled Cobras but a set of baffles came with it. I also noticed a slight power increase {& a big headache decrease} after installing the baffles.

Thanks Tropic, you would know with 3! I'm putting the baffles in tomorrow! I might even put on the stock pipes the guy gave me. As i said earlier, I have Cobras on now so do I need special brackets to put the stockers on?

[BIG--T]

I have a Standard with Cobras 6-6. I know there has to be some back pressure, but if running without baffles do I lose a significate amount of power or is it the opposite?

Back pressure isn't what increases power or efficiency, it's scavenging.  The exhaust is pulsing and contracting as it cools, and the baffles break up the pressure waves to help increase scavenging.

That is true. I think the reason why my glasspack set up works so well for me is it turned the exhaust into two 3 into 1 systems with just enough back pressure to work well. A 3 into 1 has a good scavenging effect compared to 3 singles a side.

Do you have pics of the 3-1? I'm also curious about the glasspack, where did you get it?

[RUDE DOG - Steelers]

I have the Cobras with them cut down 12 inches, no baffles.  Love the sound.   If you worried about speed this isnt the bike for you.  Its fast enough with any exhaust.  If you like the sound, thats what matters.  I personally think their way too quiet with the baffles in.  Others have stereos, I have Cobras with no baffles.

[BIG--T]

I have the Cobras with them cut down 12 inches, no baffles.  Love the sound.   If you worried about speed this isnt the bike for you.  Its fast enough with any exhaust.  If you like the sound, thats what matters.  I personally think their way too quiet with the baffles in.  Others have stereos, I have Cobras with no baffles.

Wow I bet they are loud! Yeah I bought her for the sound, smoothness, and uniquness. I wouldn't know how to measure the sound other than a db meter, but can a passenger hear you without pulling in the clutch?

[Ferris Leets]

Opinions are like assholes.  So here is mine.
   I REALLY like the flatsix sportscar sound as I make a lot of speed fast.  I've had a lot of comments about the NASCAR sound and I can pull away without pissing off everyone within a 1/2 mile.
  I was at a diner one day (lots of outside tables) when a group of about 12 Vtwins (you know the ones) left.  Between the absolutely required vroom vrooming before moving and the "rapid" acceleration, conversation on the whole block was stopped for a full minute.  Not one person commented on how nice they sounded leaving.  Just that they had left.
    Another thing. If you talk to these guys most of them think that they are getting more power from their short straight pipes.  POSERS can't stand 'em.

[BIG--T]

Opinions are like assholes.  So here is mine.
   I REALLY like the flatsix sportscar sound as I make a lot of speed fast.  I've had a lot of comments about the NASCAR sound and I can pull away without pissing off everyone within a 1/2 mile.
  I was at a diner one day (lots of outside tables) when a group of about 12 Vtwins (you know the ones) left.  Between the absolutely required vroom vrooming before moving and the "rapid" acceleration, conversation on the whole block was stopped for a full minute.  Not one person commented on how nice they sounded leaving.  Just that they had left.
    Another thing. If you talk to these guys most of them think that they are getting more power from their short straight pipes.  POSERS can't stand 'em.

Did you cut your pipes yourself, they look great. Do you still have enough room to but your baffles in if you had to?

Yeah they like to vroom and rap a lot don't they? Lol I ride with about 80 or so HD riders and a few metric twins . When I rap on mine they give me that thumbs up grin and the funny part is when we all stop, guess who admirers come up to? And there are some sharp Harleys too!l

[hubcapsc]

Opinions are like assholes.  So here is mine.
   I REALLY like the flatsix sportscar sound as I make a lot of speed fast.  I've had a lot of comments about the NASCAR sound and I can pull away without pissing off everyone within a 1/2 mile.
  I was at a diner one day (lots of outside tables) when a group of about 12 Vtwins (you know the ones) left.  Between the absolutely required vroom vrooming before moving and the "rapid" acceleration, conversation on the whole block was stopped for a full minute.  Not one person commented on how nice they sounded leaving.  Just that they had left.
    Another thing. If you talk to these guys most of them think that they are getting more power from their short straight pipes.  POSERS can't stand 'em.

Did any car alarms go off? I was going in someplace once, a couple of dudes came out, cranked their Harleys and car alarms went off... they're either deef or
don't ride more than a half mile at a time...

-Mike "my head hurts"

[X Ring]

Mike, they actually like setting of the car alarms.

Marty

[BIG--T]

Opinions are like assholes.  So here is mine.
   I REALLY like the flatsix sportscar sound as I make a lot of speed fast.  I've had a lot of comments about the NASCAR sound and I can pull away without pissing off everyone within a 1/2 mile.
  I was at a diner one day (lots of outside tables) when a group of about 12 Vtwins (you know the ones) left.  Between the absolutely required vroom vrooming before moving and the "rapid" acceleration, conversation on the whole block was stopped for a full minute.  Not one person commented on how nice they sounded leaving.  Just that they had left.
    Another thing. If you talk to these guys most of them think that they are getting more power from their short straight pipes.  POSERS can't stand 'em.

Did any car alarms go off? I was going in someplace once, a couple of dudes came out, cranked their Harleys and car alarms went off... they're either deef or
don't ride more than a half mile at a time...

-Mike "my head hurts"

Hey Mike, Been riding a lot? It sure has been beautiful weather but not sure about this weekend. Did you go on the treehouse ride? Hope all is well.  What did you say? Huh?

[hubcapsc]

Hey Mike, Been riding a lot? It sure has been beautiful weather but not sure about this weekend. Did you go on the treehouse ride? Hope all is well.  What did you say? Huh?

Me and one of the other Mikes went to the Congaree Swamp last weekend, and I went near an active tornado
on the way home, I was on one side of Lake Greenwood, and it was on the other... crazy wind...



I'm headed to Texas with the Tennessee boys for the GOTF in about a week...

-Mike

[mirion]

Its fast enough with any exhaust.  If you like the sound, thats what matters.

I totally agree with Steelers. Unless you make your living from speed, whats a few horsepower among friends. I have Cobras on one and fully adjustable Mark T Glasspacks with Trombones on the other. Somedays the bike I chose is based entirely on the sound I want to hear. The Interstate with glasspacks will beat the 97 with Cobras I think, according to my butt dyno, but who cares. I don't believe in any modifications for the sake of a couple HP that will mess with the dependability of a Honda that goes fast enough.

Some of my favorite riding buddies are V Twinner's and my favorite jab is:
Harley Davidson, the most efficient way to convert gasoline to noise without the side effects of horsepower.

[Redline +]

I have a Standard with Cobras 6-6. I know there has to be some back pressure, but if running without baffles do I lose a significate amount of power or is it the opposite?

When I purchased my 2002 it had Cobra pipes. Butt dyno felt an increase in performance with the baffles out. Chassis dyno confirmed an increase of 5hp/5lbs with open pipes. YMMV.

Run stock IS pipes now.

Redline 

[Mildew]

They say each bike is different. I really think my bike runs better with the cobras. I know the fuel milage increased. I'd love to take the baffles out but I hear it's not an easy task with the carbon build up.

[BIG--T]

They say each bike is different. I really think my bike runs better with the cobras. I know the fuel milage increased. I'd love to take the baffles out but I hear it's not an easy task with the carbon build up.

I haven't had my 98 long, but the first thing i done when I got her home was remove the baffles. It has had the baffles in for 13 years and I took the screws out, inserted a hooked shaped  coat hanger, couple of jerks and she was out with no problem. If it's real stuborn, spray some penetrating oil and let it set a while. I doubt if it will need oil if it gas been garaged. BTW what is your mpg and is it an I/S?
Thanks

[BIG--T]

Hey Mike, Been riding a lot? It sure has been beautiful weather but not sure about this weekend. Did you go on the treehouse ride? Hope all is well.  What did you say? Huh?

Me and one of the other Mikes went to the Congaree Swamp last weekend, and I went near an active tornado
on the way home, I was on one side of Lake Greenwood, and it was on the other... crazy wind...



I'm headed to Texas with the Tennessee boys for the GOTF in about a week...

-Mike

Man you were lucky! I saw the after effects Sunday. We rode all day Saturday and it was hot and sunny but when we crossed the Anderson/ Pickens county line coming back home around 5:30, it turned black and knew we were gonna get soaked, but didn't get a drop

Mike What is the GOTF? Anyway hope ya'll have a great trip and stay safe!
Tony

[Tropic traveler]

Many moons ago the LH muffler on my '97 started to rattle inside. It was annoying. After doing lots of looking at the Shop Talk section of this site I decided to make my own glasspack set up.
The 3 into 1 effect I speak of is just the 3 little pipes coming from the stock headpipe dumping into the collector I made to shrink down to the 2" ID glasspack. The glasspacks are just a set of cheapie no-name muffler shop brand turned the way they are supposed to be, with the "cups" facing the exhaust flow. Part of my research {thanks old timer Valk guys! } showed that 2" ID was the right size to get as close to stock back pressure as possible. The glasspacks have a nice mellow sound that is not offensive to most folks & stays pretty mild until you twist it hard. Sounds like a high priced Eye-talian car at full song, 
Here's a pic of the GP exhaust.


Later on I added about a foot of 2" pipe with a funky tip as an extension to cut down on the droning effect the GP's had by dumping the sound into the 4" tips I had made. Seems to have worked, the droning has gone away. I purposely welded the tips {from a Lincoln} kinda offset & sloppy to give it just a bit more turbulence & backpressure. 



I like the way it turned out.

[Tropic traveler]

BTW, if you are not into fabricating stuff like I am, the MarKT "Trombones" exhaust is a very clever, really cool design that IMHO has the best of both worlds. Mellow glasspack sound or a really rude straightpipe sound when you want it. 
Well worth looking into! 

Cruise all day.. then scare the Harleys away!!!  

[BIG--T]

Yours look great! As far as being a fabricator, that's about all I've ever done. Now I've got to find  out about the Mark T Trombone..got me curious

[John U.]

Here's a link to his website: http://horseapple.com/

[rodeo1]

my kid bro cobras were knocking his already viet nam ptsd, screwed up hearing out on long rides, so here is what i did to them for him.

i took the baffles out and welded a freeze plug onto the end of each one, then drilled a 3/4 inch hole on each freeze plug, then wrapped the baffles in fiberglass packing material about 1/4 inch thick. tied it with stainless steel safety wire and re inserted them, it still has that 454 chevy sound but way mellower, and don't drive him to drink doing 500 mile days.

and a valk don't need loud pipes to scare a harley owner, they are way too intimidated already.

[Mildew]

They say each bike is different. I really think my bike runs better with the cobras. I know the fuel milage increased. I'd love to take the baffles out but I hear it's not an easy task with the carbon build up.

I haven't had my 98 long, but the first thing i done when I got her home was remove the baffles. It has had the baffles in for 13 years and I took the screws out, inserted a hooked shaped  coat hanger, couple of jerks and she was out with no problem. If it's real stuborn, spray some penetrating oil and let it set a while. I doubt if it will need oil if it gas been garaged. BTW what is your mpg and is it an I/S?
Thanks

I have a tourer. I used to get 29 mpg I get 33 running hard and up to 38 running easy. I did get 29 a few times when I first put the cobras on but I think it was my wrist. I don't know what happened but my fuel milage got better

[Mildew]

Well, I just took my baffles out. 

[BIG--T]

Well, I just took my baffles out. 

How you like the sound now??

[Mildew]

  Sounds great!. It sounds faster. lol. My wife is going to kill me. If she don't my neighbors will. Expecially the one that shot the Dominos delivery guy for driving too fast.  

[Mildew]

I just got back from my test ride. I do notice a power loss but it's no biggie here on the east coast. You cant run off from a bicycle with all this traffic. I'll probably be putting my baffles back in soon but for now I'll be ridding around with this chit eatin grin. 

[BIG--T]

I just got back from my test ride. I do notice a power loss but it's no biggie here on the east coast. You cant run off from a bicycle with all this traffic. I'll probably be putting my baffles back in soon but for now I'll be ridding around with this chit eatin grin. 

Ha ha, enjoy it while you can and might oughta wear some body armour in case your neighbor freaks out again, ummm, if your wife don't get you first!  I just noticed your avatar. Was that wheelie after you pulled the baffles out?

[RUDE DOG - Steelers]

I have the Cobras with them cut down 12 inches, no baffles.  Love the sound.   If you worried about speed this isnt the bike for you.  Its fast enough with any exhaust.  If you like the sound, thats what matters.  I personally think their way too quiet with the baffles in.  Others have stereos, I have Cobras with no baffles.

Wow I bet they are loud! Yeah I bought her for the sound, smoothness, and uniquness. I wouldn't know how to measure the sound other than a db meter, but can a passenger hear you without pulling in the clutch?

I really dont ride with a passenger too often.  I really dont think my Cobras are obnoxiously loud. I think they are a good loud, like a small block.  Nothing like an open pipe V-twin.  When I had my pipes cuts down, I marked spots and had wholes drilled so I can put the baffles in again if I want to.  Personally I dont think Cobras are loud at all with the baffles in.  I really think the volume of the Cobras is overstated. 

[RUDE DOG - Steelers]

Opinions are like assholes.  So here is mine.
   I REALLY like the flatsix sportscar sound as I make a lot of speed fast.  I've had a lot of comments about the NASCAR sound and I can pull away without pissing off everyone within a 1/2 mile.
  I was at a diner one day (lots of outside tables) when a group of about 12 Vtwins (you know the ones) left.  Between the absolutely required vroom vrooming before moving and the "rapid" acceleration, conversation on the whole block was stopped for a full minute.  Not one person commented on how nice they sounded leaving.  Just that they had left.
    Another thing. If you talk to these guys most of them think that they are getting more power from their short straight pipes.  POSERS can't stand 'em.

I can pull away also without pissing anyone off within a half mile.  That has less to do with the exhaust and more to do with the person twisting the throttle.

[Mildew]

I just got back from my test ride. I do notice a power loss but it's no biggie here on the east coast. You cant run off from a bicycle with all this traffic. I'll probably be putting my baffles back in soon but for now I'll be ridding around with this chit eatin grin.  

Ha ha, enjoy it while you can and might oughta wear some body armour in case your neighbor freaks out again, ummm, if your wife don't get you first!   I just noticed your avatar. Was that wheelie after you pulled the baffles out?

That wheelie is from a while ago but I'm sure I would have no problem with the baffles out. Its more timing and technique than power to do that kind of thing. The power loss noticable but it still has plenty enough for me. I like the sound better with the baffles out but I probably put them in when I travel on a long trip

[BIG--T]

I just got back from my test ride. I do notice a power loss but it's no biggie here on the east coast. You cant run off from a bicycle with all this traffic. I'll probably be putting my baffles back in soon but for now I'll be ridding around with this chit eatin grin.  

Ha ha, enjoy it while you can and might oughta wear some body armour in case your neighbor freaks out again, ummm, if your wife don't get you first!   I just noticed your avatar. Was that wheelie after you pulled the baffles out?

That wheelie is from a while ago but I'm sure I would have no problem with the baffles out. Its more timing and technique than power to do that kind of thing. The power loss noticable but it still has plenty enough for me. I like the sound better with the baffles out but I probably put them in when I travel on a long trip

Yeah it is not bad and to me not that loud riding normally. I can talk to my wife with no problem just cruising, but stopping and revving or just hitting her hard- she's loud but sounds sooo good!

[Ferris Leets]

Opinions are like assholes.  So here is mine.
   I REALLY like the flatsix sportscar sound as I make a lot of speed fast.  I've had a lot of comments about the NASCAR sound and I can pull away without pissing off everyone within a 1/2 mile.
  I was at a diner one day (lots of outside tables) when a group of about 12 Vtwins (you know the ones) left.  Between the absolutely required vroom vrooming before moving and the "rapid" acceleration, conversation on the whole block was stopped for a full minute.  Not one person commented on how nice they sounded leaving.  Just that they had left.
    Another thing. If you talk to these guys most of them think that they are getting more power from their short straight pipes.  POSERS can't stand 'em.

I can pull away also without pissing anyone off within a half mile.  That has less to do with the exhaust and more to do with the person twisting the throttle.

   I agree but,  What I meant was that I can accelerate RAPIDLY with the Valk  and still not make the noise those bikes made.  The wrist is rather like a volume control.  My Nomad had the 2 into 1 Roadhouse system.  At moderate wrist it was pretty quiet.  With full wrist it was pretty loud.  Not that annoying blat but more of a steady roar. (Very satisfying)

[Tropic traveler]

Quote from the Rude Dog...
"I can pull away also without pissing anyone off within a half mile.  That has less to do with the exhaust and more to do with the person twisting the throttle."

I agree!
We have an azzhat in my neighborhood who owns one of those legendary, full of heritage & tradition American company bikes. It seems that he knows nothing but the 10 minute throttle blipping warm ups, full throttle wind 'er out in every gear upon both departures & arrivals type of riding.
It is all about respect for your fellow residents, some folks just don't have any.

[BIG--T]

Quote from the Rude Dog...
"I can pull away also without pissing anyone off within a half mile.  That has less to do with the exhaust and more to do with the person twisting the throttle."

I agree!
We have an azzhat in my neighborhood who owns one of those legendary, full of heritage & tradition American company bikes. It seems that he knows nothing but the 10 minute throttle blipping warm ups, full throttle wind 'er out in every gear upon both departures & arrivals type of riding.
It is all about respect for your fellow residents, some folks just don't have any.

Yeah all bark and no bite!   Hey I see you parted out the trike