Author Topic: How loud are these pipes?  (Read 5704 times)

0 Members and 4 Guests are viewing this topic.

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,805
Re: How loud are these pipes?
« Reply #25 on: March 14, 2006, 12:27:03 PM »
For the sake of more argument, could a guy quiet down a pipe like this?  It has a baffle with fiberglass wrapping already -- but the center of the pipe is wide open.  Could a more restrictive baffle be fashioned to fit in the current pipe?  Anyone done this?

That's a good question... OKAY, agruments aside, does anyone have an answer to this question.  It would be very interesting to learn if it is possible. My initial thought would be that it would cause too much back presure... but maybe not.

Anyone?
Not SOHC4, but an applicable experience.
I was given a CX500 with a fairly new MAC 2 into 1 installed on it.  When I eventually got it running, I found out that the, pipe was REALLY loud.  Not wanting to risk further bouts with tinitus, I set about quieting the beast (while wearing earplugs). 

Deconstruction:
The "baffle" was simply a perforated tube with some holes in it to allow some noise to enter the outer megaphone chamber and reverberate in there.  You could see the full diameter of the perforated tube the entire length of the "muffler".  Okaaaay..... low restriction.

I packed the outer chamber with steel wool.  This helped damp and soften the noise a bit.  And, the engine ran better with the added restriction since the carbs had not been rejetted from stock configuration.  But, the exhaust shock waves and heat eventually resulted in blowing bits of glowing steel embers out the back.  After making and destroying a list of people to drive ahead of... I did some online research of muffler designs.

Striking a balance between sound and restriction is not easy.  Steel wool and fiberglass muffle sound by creating turbulence that distorts the sound wave pulses from the engine ports.  The more turbulence, the more sound damping as the waves distort into each other and cancel themselves out.  However, turbulence is restrictive to exhaust flow.  I learned that the less restrictive exhaust designs have no packing of fiberous materials because of the flow restricting turbulance created.  Instead they use strategic placement of angled baffles to redirect exhaust flow with minimal restriction, yet reflect sound pulses in the reverse direction so they may cancel.   A balance is struck between multiple baffle stages and the desired restriction of air flow.

After learning this, I re-examined the Mac muffler design with an eye toward baffle insertion and placement.  Let's see, trial and error method, or do the math for exhaust impulse timing/distance traveled over multiple RPMs to determine baffle placement and spacing.

Then I found a nearly new stock exhaust system, designed and implemented by Honda complete with balance box and strategic baffling, on eBay for what I now considered a reasonable price (given my recent illumination).  I installed that and am happy to report no re-occurance of tinitus.
And guess what!  The stock carb jetting (aleady installed) works perfectly with the stock exhaust!  So, the engine runs MUCH better over teh entire range, too!

The only drawback, is that I now have to find someone to buy a really loud CX500 exhaust system in really good condition, hopefully far away from where I live in California (sound travels, you know).

Cheers,
And, Good luck!

Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Zeke

  • Hot Shot
  • ***
  • Posts: 277
Re: How loud are these pipes?
« Reply #26 on: March 14, 2006, 07:05:06 PM »
Well, obviously the thing to do is to try them first.  I'll need to at least do some jetting to make sure I don't run too lean.  If they are too loud then on to plan b.

I have a friend with an extra supertrapp.  Don't know if it'll fit, but it should be interesting to look at that system -- shouldn't be too hard to work out something similar to dull it down a bit.

The tuning part worries me a bit -- my bike is already pretty smooth, and it sounds like that might suffer a bit.  I only rap it up above 7500 rpm occasionally when I'm coming home from work in the twisties, so if that's where all the power comes from could be a bit disappointing.  But waddaya do, my 4-4s are falling apart!

Zeke

cd811

  • Guest
Re: How loud are these pipes?
« Reply #27 on: March 14, 2006, 07:24:23 PM »
what?


what?


what did he say?


I couldn't hear him...


what?

Offline mrbreeze

  • Not your average
  • Really Old Timer ...
  • *******
  • Posts: 5,902
  • Shut up when you're talkin' to me!!
Re: How loud are these pipes?
« Reply #28 on: March 14, 2006, 07:35:42 PM »
Well....I think I will just take my Bozo ass out to the garage and rev up my scoot with my open Kerker 4to1.If anyone comes over to complain,I'll probably just light a cig and blow some smoke in their face!!!
MEMBER # 257
Fool me once..shame on you. Fool me twice..I'm kickin' your a$$......

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,805
Re: How loud are these pipes?
« Reply #29 on: March 14, 2006, 09:54:36 PM »
Well....I think I will just take my Bozo ass out to the garage and rev up my scoot with my open Kerker 4to1.If anyone comes over to complain,I'll probably just light a cig and blow some smoke in their face!!!

I hope that's a promise, because I think that's really a good plan!  The word is that police officers really enjoy that immensely.  They just love paling around with a true badass who won't take any guff from anybody.   Let us know how you make out with your new friend.  And, don't forget the big red nose and big shoes, too.  Guaranteed to break the ice at bookings!

Best of luck,

 ;D ;D
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline mrbreeze

  • Not your average
  • Really Old Timer ...
  • *******
  • Posts: 5,902
  • Shut up when you're talkin' to me!!
Re: How loud are these pipes?
« Reply #30 on: March 15, 2006, 12:06:48 AM »
Say what??????????????????
MEMBER # 257
Fool me once..shame on you. Fool me twice..I'm kickin' your a$$......

Offline mrbreeze

  • Not your average
  • Really Old Timer ...
  • *******
  • Posts: 5,902
  • Shut up when you're talkin' to me!!
Re: How loud are these pipes?
« Reply #31 on: March 15, 2006, 12:10:01 AM »
I guess I'll have to look out for officer Two Tired with my hardley loud 2 wheeler!!!! (To each his own!!!!)
MEMBER # 257
Fool me once..shame on you. Fool me twice..I'm kickin' your a$$......

Offline ofreen

  • Old Timer
  • ******
  • Posts: 4,029
Re: How loud are these pipes?
« Reply #32 on: March 15, 2006, 12:44:09 AM »
It looks to me that people who choose to subject other people to their unwelcome loud noises, whether exhausts, music, or whatever, fall into to two categories.  In the first category are those who are in desperate need of attention (maybe due to perceived or real sexual inadequacy, or maybe their mama didn't breast-feed them), so loud exhausts are a way of saying "Look at me. I'm not either a dork."  In the second category are those who may have no particular ego problems, but are simply inconsiderate of others.

For a long time, I fell into the second category.  I like the sound of engines in all their variety.  It is easier to appreciate that variety if they are not muffled down to the sound level of a sewing machine.  When I was a kid, I took the muffler off of my S90 and replaced it with a steel tube from an old vacuum cleaner.  I probably pissed more than a few people off with that thing, but didn't care because it suited me.  Later on, I put straight pipes on an SL350 and rode it on the street.  I remember passing cars and hearing the sound of the exhaust reflecting loudly off the side of the car.  Yee-haw!

At some point, I realized that if everybody just does as they please with no consideration for others, the world becomes a #$%*ty place to live.  I still enjoy the sound of a well-tuned exhaust, but there is a time and a place.  A few years ago, I had a GSX-R1100 with few mods, including a Kerker pipe and the Comp III baffle.  As long as I stayed out of throttle in civilized areas and kept the revs down, it bothered nobody.  But out away from crowded areas, I could ring it out and have some fun.  It is possible, you just have to have some consideration for other people and use a little discretion.
Greg
'75 CB750F

"I would rather have questions I cannot answer than answers I cannot question." - Dr. Wei-Hock Soon

Offline mrbreeze

  • Not your average
  • Really Old Timer ...
  • *******
  • Posts: 5,902
  • Shut up when you're talkin' to me!!
Re: How loud are these pipes?
« Reply #33 on: March 15, 2006, 01:03:26 AM »
Hey,right on Ofreen...I never said I was out to be obnocious to my fellow brothers & sisters out there on the road.I really don't think it is that teribibly loud compared to alot of the Harleys you hear go by but hey....I don't think I need to go out and pay $1000 and up to find stock exhaust to make it butt quiet either.I am not trying to bring any kind of attention to myself as some have posted here and I think that is alot of bull#$%* brought up in the first place.I am not running a chopped off full blast pipe.I have a 4to 1 megaphone that has no baffle and I think if it was that extreme,I would have already been pulled over and ticketed for loud exhaust(Yeah Too Tired-right here in Modesto,California)
MEMBER # 257
Fool me once..shame on you. Fool me twice..I'm kickin' your a$$......

Offline ofreen

  • Old Timer
  • ******
  • Posts: 4,029
Re: How loud are these pipes?
« Reply #34 on: March 15, 2006, 01:26:38 AM »
Hey,right on Ofreen...I never said I was out to be obnocious to my fellow brothers & sisters out there on the road.

I believe you.  My comments weren't directed toward you or anybody else on this forum.  Some of it was intended to be humorous.
Greg
'75 CB750F

"I would rather have questions I cannot answer than answers I cannot question." - Dr. Wei-Hock Soon

Offline bill440cars

  • Feeling More & More,
  • Really Old Timer ...
  • *******
  • Posts: 12,358
  • Tryin' To Slow Down "Time"!
Re: How loud are these pipes?
« Reply #35 on: March 15, 2006, 07:33:17 AM »

         Personally (and of of course this is only my opinion), I like a bike with some sound (not blasting like a
     H-D, just a good sort of gutsy sound) from megaphone/s. A bike with a stock type 4 into 4 would
     be nice at times but, there are also times that I like to hear, what I call, music from the pipes. I
     don't know if I could handle open exhaust, even on a Honda. I do know that I do not like the
     sound from most H-Ds. Just my two cents. Later on, Bill :) ;)
Member # 1969
PRAYERS ALWAYS FOR: Bre, Jeff & Virginia, Bear, Trevor & Brianna ( Close Friend's Daughter)
"Because HE lives, I can Face Tomorrow"                  
 You CAN Teach An Old Dog New Tricks, Just Takes A Little Bit Longer & A Lot More Patience!! 
             
Main Rides: '02 Durango, '71 Swinger & Dad's '93
                  Dakota LE 4x4 '66 CB77 & '72 SL350K2
Watch What You Step Into, It Could  End Up A Mess!

Offline chippyfive50

  • Hot Shot
  • ***
  • Posts: 405
  • NO PEE ON TEPEE
    • thesweetimpala
Re: How loud are these pipes?
« Reply #36 on: March 15, 2006, 08:01:50 AM »
i replaced my horn with open pipes, fun gauge showed 100% gain ;D
SOHC Member#4000
71' 500K0 #1021237--E1108327
78' 550
72' 750K2(sold to "Craig")
74' 750K4 #2306334--E2303422
73' CL175
http://gallery.sohc4.net/main.php?g2_itemId=14013

Offline heffay

  • Really Old Timer ...
  • *******
  • Posts: 7,874
Re: How loud are these pipes?
« Reply #37 on: March 15, 2006, 12:12:56 PM »
I'm with ya bill.  i like a bike that sounds like its got a bit of meat on its bones. 

i also wouldn't say i do it out of lack of respect for people (that's a bull#$%* excuse for people that can't handle a bit of noise)
but, rather, for the people that like the sound of a bike going past (although, i really don't take other peoples opinions of MY bike seriously anyway)

you see, i live on one of the best twisty roads in colorado... if i couldn't sit at my computer and look out my big living room window with the summer breeze bringing in all the wonderful bike sounds from the road... i'd be much less thrilled to live where i live!
Today: '73 cb350f, '96 Ducati 900 Supersport
Past Rides: '72 tc125, '94 cbr600f2, '76 rd400, '89 ex500, '93 KTM-125exc, '92 zx7r, '93 Banshee, '83 ATC250R, 77/75 cb400f

Offline bill440cars

  • Feeling More & More,
  • Really Old Timer ...
  • *******
  • Posts: 12,358
  • Tryin' To Slow Down "Time"!
Re: How loud are these pipes?
« Reply #38 on: March 15, 2006, 03:27:12 PM »

     Hey heffay, back in the early 80's, I used to hear a Kawasaki 900 Z1 (with a Kerker 4into1) go through the gears on a back road close to my house. It sounded like pure music to my ears and you could hear it gear. I had a CB72 250cc Hawk back in 68-69' with megaphones that had removable plates on the ends and I'm telling you that, to me, it wasn't noise at all. It was all music to my ears.
I would get out of town, pull the plates and roll on.  Gotta go, later on. Bill
Member # 1969
PRAYERS ALWAYS FOR: Bre, Jeff & Virginia, Bear, Trevor & Brianna ( Close Friend's Daughter)
"Because HE lives, I can Face Tomorrow"                  
 You CAN Teach An Old Dog New Tricks, Just Takes A Little Bit Longer & A Lot More Patience!! 
             
Main Rides: '02 Durango, '71 Swinger & Dad's '93
                  Dakota LE 4x4 '66 CB77 & '72 SL350K2
Watch What You Step Into, It Could  End Up A Mess!

Offline jph550

  • Enthusiast
  • **
  • Posts: 104
Re: How loud are these pipes?
« Reply #39 on: February 16, 2010, 10:21:16 PM »
For the sake of more argument, could a guy quiet down a pipe like this?  It has a baffle with fiberglass wrapping already -- but the center of the pipe is wide open.  Could a more restrictive baffle be fashioned to fit in the current pipe?  Anyone done this?
...less restrictive exhaust designs have no packing of fiberous materials because of the flow restricting turbulance created.  Instead they use strategic placement of angled baffles to redirect exhaust flow with minimal restriction, yet reflect sound pulses in the reverse direction so they may cancel.   A balance is struck between multiple baffle stages and the desired restriction of air flow.

After learning this, I re-examined the Mac muffler design with an eye toward baffle insertion and placement.  Let's see, trial and error method, or do the math for exhaust impulse timing/distance traveled over multiple RPMs to determine baffle placement and spacing.

Then I found a nearly new stock exhaust system, designed and implemented by Honda complete with balance box and strategic baffling, on eBay


Two Tired, what model did you find this from. I'm interested in quieting my 4-1 and have been looking at baffles and am quite baffled.
Thanks,
Jason
'76 cb550K
with original faded brown/green tank

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,805
Re: How loud are these pipes?
« Reply #40 on: February 16, 2010, 10:39:15 PM »
Jason,
That excerpt (quote) is from a post talking about a CX500 exhaust, where I bought a used stock type off an eBay member.

The quietest 4 into 1 I've heard for the 550 is the stock one from Honda.  The quietest 4 into 4, is the stock 77-78 Cb550K set.

I don't know that any aftermarket types made any claim toward a quieter exhaust.  In fact, I think they consider it a sales killer, as those who want a new exhaust, more often than not want it louder, and they (the aftermarket manufacturers) don't have to be concerned about federal or state noise level adherence.  That responsibility is passed on to the consumer.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Sam Green Racing

  • Really Old Timer ...
  • *******
  • Posts: 16,068
  • I REALLY? hate black rims.
Re: How loud are these pipes?
« Reply #41 on: February 16, 2010, 10:44:06 PM »
Ya must have a good memory Lloyd ;D ;D ;D ;D ;D ;D

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline jph550

  • Enthusiast
  • **
  • Posts: 104
Re: How loud are these pipes?
« Reply #42 on: February 16, 2010, 10:49:24 PM »
Thanks for your response Two Tired, I was curious what pipe you found to replace the MAC on your CX500. maybe it was a stock type for the CX? Thought I could examine its specs and try to apply its baffling to my MAC guessing it may be better than what i have now.
If this doesn't help, I'll look for a stock four into four since I'm on a K and don't want to deal with the kickstart unless I find an F parts bike with good exhaust.
peace, Jason
'76 cb550K
with original faded brown/green tank

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,805
Re: How loud are these pipes?
« Reply #43 on: February 16, 2010, 11:01:26 PM »
Thanks for your response Two Tired, I was curious what pipe you found to replace the MAC on your CX500. maybe it was a stock type for the CX?
Yes, it was a nearly new stock Honda exhaust system for the Honda CX500.  Which was convenient, as it was a CX500 I put it on.   ;D ;D

Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,805
Re: How loud are these pipes?
« Reply #44 on: February 16, 2010, 11:08:24 PM »
Ya must have a good memory Lloyd ;D ;D ;D ;D ;D ;D

Sam. ;)

It (the memory) seems to be selective, these days.  It works better if tied to some visual image.  Don't ask me about names and dates.

What was your name again?   ;D ;D

I remember faces quite well.  Even when they age.  (Young'uns probably won't understand that last bit.  I wouldn't have when I was young!)  ;D ;D
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Sam Green Racing

  • Really Old Timer ...
  • *******
  • Posts: 16,068
  • I REALLY? hate black rims.
Re: How loud are these pipes?
« Reply #45 on: February 16, 2010, 11:15:35 PM »
I've never seen your face Lloyd.....on the other hand, your hands are quite memorable.
 ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline jph550

  • Enthusiast
  • **
  • Posts: 104
Re: How loud are these pipes?
« Reply #46 on: February 16, 2010, 11:19:17 PM »
Thanks for your help and answers. If I'm successfull with the MAC I'll report back. I have good ear plugs, but after a day of riding, ear plugs hurt your ears too, though in a different way than noise.
Jason
'76 cb550K
with original faded brown/green tank

Offline faux fiddy

  • Just becaus I'm the second post on the pissed off thread doesn't mean I'm an
  • Old Timer
  • ******
  • Posts: 4,812
  • bike in a box
Re: How loud are these pipes?
« Reply #47 on: February 17, 2010, 04:49:59 AM »
No need to quote the wisdom of posts of TT about earplugs, cops, and  the  psychological need for  attention. I also understand the concept of run whatchya brung,'  but no one has mentioned the  southpark  episode  addressing the loud  bike  Flagrant  Attention Getters, or "FAGS", as the Southpark kids and residents came to call them.

http://www.southparkstudios.com/guide/1312/?

I hear that episode was discussed extensively on other sportbike forums.
^^^^^^^/l^^^^^^^^^^^^^^/l^^^
. . ______/ l_________________/  l
<'  '  '   '  o .  . . . . . . .................(
 ' VVVVV'   ')))))____>-''''''''''''''''''\  l
' . vvvv_   -              -                 \/

Offline SteveD CB500F

  • Global Moderator
  • Old Timer
  • *****
  • Posts: 4,553
  • Ride on the Steel Breeze...
    • TVAM
Re: How loud are these pipes?
« Reply #48 on: February 17, 2010, 08:10:25 AM »
What is that in your signature poor boi?
SOHC4 Member #2393
2015 Tiger 800 XRT
1971 CB500K0 (US Model)

Offline my78k

  • I am Meat-O of the Hungry Horses MC
  • Old Timer
  • ******
  • Posts: 2,839
Re: How loud are these pipes?
« Reply #49 on: February 17, 2010, 08:16:46 AM »
A shark?