Riders Of Vision

General => TechTalk => Topic started by: acee125 on May 16, 2008, 06:11:06 PM

Title: Open Exhaust...?
Post by: acee125 on May 16, 2008, 06:11:06 PM
It looks like it's gonna be a while before my Mac's show up and with fresh rubber and great weather I'm itching to go riding. However, I'm sick of my bike being so quiet.

Would it hurt my bike at all if I ran it without mufflers and had no exhaust from the manifold back?

I would assume that the bike would need to be jetted a bit richer although it seems that the concensus on ROV is that you don't HAVE to rejet after you install Mac's.

Is it safe to assume that Mac's and the stock exhaust with no mufflers would have appoximately the same amount of flow?

Would I be taking an unnecessary chance of burning a valve with so little exhuast or would my bike just be extremely loud?
Title: Re: Open Exhaust...?
Post by: Brian Moffet on May 16, 2008, 06:32:27 PM
I believe the stock mufflers (complete, everything) and the Macs have the same flow.  If I remember correctly, there should be no jetting changes from the standard entire exhaust and the macs.

I would worry about not have exhaust, you'll be dumping an incredible amount of heat right at battery level from the rear Y pipe.  I think pulling the exhaust would be a really unsafe and bad idea.

I'm not so sure why you're sick of your bike being so quiet, that baffles me.

edit: I just did the math, and the exhaust temperatures at the Y-joint would be around 1300 degrees Fahrenheit.  That's enough to move some steels from elastic deformation into plastic deformation.  I.e it will bend and not return to the original shape...

Brian
Title: Re: Open Exhaust...?
Post by: kiawrench on May 16, 2008, 07:02:46 PM
been there, did that - if you are going to run open collector, get ready to buy wiring harness,battery ,r/r rear tire ,bushings/maybe bearings --- you can, (not will ) destroy the bike by just jumping out there and running open headers
Title: Re: Open Exhaust...?
Post by: acee125 on May 16, 2008, 07:09:22 PM
Brian and kiawrench,

I see the error of my original post and should have taken a closer look at my exhuast before I posted. I thought that you could remove just the "cans" from the manifold but upon closer inspection I found that they are welded to it. (at least mine are)

As far as wanting to make it louder? I'll blame it on my youth. Why did people put glasspacks on muscle cars in the 60's and 70's and why to people straight pipe harleys? Because when done right, I think it sounds cool. I know that opinion is not shared by all and that's ok.

Respectfully,

Acee125
Title: Re: Open Exhaust...?
Post by: h2olawyer on May 16, 2008, 07:10:13 PM
I agree with Brian.  Loud bikes mostly serve just to annoy the non-riding public, further damaging our reputation.  About the only 'safety' argument to be made is to give an audible signal to unwary pedestrians.  The sound basically flows in a cone shape to the rear of the bike.  Well over 90% of the auto - bike accidents come from the front or side.  Your horn makes a much better signal to them than an exhaust ever would.

If bikes keep getting louder, look for tighter enforcement of existing noise statutes, tougher laws & even arguments to ban bikes.  What would you rather do - self police in this issue or become an accomplice to further restrictions in our right to ride?

As you can tell, loud bikes are kind of an 'issue' with me.  Unlike Rick_G, I actually like the sound from our OEM exhaust.  I don't think it "sounds like a Hoover with a head cold".   ;)

As for damage to the bike, I wouldn't do it.  No sense in taking the risks.

H2O
Title: Re: Open Exhaust...?
Post by: acee125 on May 16, 2008, 07:30:25 PM
Quote from: acee125 on May 16, 2008, 07:09:22 PM
I see the error of my original post and should have taken a closer look at my exhuast before I posted. I thought that you could remove just the "cans" from the manifold but upon closer inspection I found that they are welded to it. (at least mine are)

Yes, upon further examination I think it would be ridiculous to run the bike with open exhaust because of many already mentioned problems it would pose.

As far as noise is concerned: Ridiculously loud bikes are only good for one thing: showing off to whoever it is you want to please. Other than that they'll just make you deaf if you have to listen to it at speed and annoy cage drivers while you're at it.

However...I'm still a fan of moderate to loud bikes. IMHO, they sound cooler and in most cases free up horsepower. When I rev my V either while stationary or on the go I hear mainly engine noise, I also want to hear my exhaust. Thus, get a new set of pipes.

For me, the ideal exhaust is one that is loud when you rev it, and mellows out into a nice tone when cruising. I would guesstimate that 60 to 80 percent of bikes with aftermarket exhaust fall into that catagory.
Title: Re: Open Exhaust...?
Post by: Brian Moffet on May 16, 2008, 07:34:32 PM
Quote from: acee125 on May 16, 2008, 07:30:25 PM
in most cases free up horsepower.

Actually, there have been some tests done with aircraft (which tend to run straight pipes).  Turns out that a quieter tuned exhaust will provide more power than the straight pipes.  There is a company that is making tuned exhaust for general aviation aircraft and seeing 15 percent HP increases.  (http://www.powerflowsystems.com/exhaust_process.php is what they have).  While I could not argue that the Vision exhaust has been tuned to nearly the level that power flow systems has done for aircraft, it is an interesting idea.

Brian
Title: Re: Open Exhaust...?
Post by: acee125 on May 16, 2008, 07:45:47 PM
Quote from: Brian Moffet on May 16, 2008, 07:34:32 PM

Turns out that a quieter tuned exhaust will provide more power than the straight pipes.  There is a company that is making tuned exhaust for general aviation aircraft and seeing 15 percent HP increases.  Brian

It all depends on what you're trying to accomplish. Like you said, exhausts can be tuned. Generally for power delivery and the desired RPM range you want the power in. And yes, they can be made to run quiet and still produce if not increase power. The quiet factor of the airplace exhaust you gave example of is not the source of the power increase but a byproduct of its design.

It's the same reason that long tube headers result in more horsepower than "shorty" headers and why Flowmaster's "Delta" series mufflers can stay reasonably quiet while gaining horsepower over OEM mufflers.

Title: Re: Open Exhaust...?
Post by: h2olawyer on May 16, 2008, 08:11:01 PM
Most current noise ordinances permit aftermarket exhaust only if they are no louder than the stock exhaust.  They are also graduated, allowing more noise for older vehicles.  That said, the laws aren't heavily enforced in too many places.  I know Colorado Springs has equipped their police force with db meters and began aggressive enforcement a couple years ago.  Even guys with aftermarket cans on sportbikes (which are not normally that annoying) have been forced to reinstall their stock exhaust.

H2O
Title: Re: Open Exhaust...?
Post by: QBS on May 16, 2008, 09:24:53 PM
Regarding aftermkt. cans on sprtbikes:  Several years ago Motorcycle Consumer News did before and after dynometer testing on several 1000 c.c. sport bikes of the day equiped with various aftermkt. systems.  They found that more loud=sometimes, a little more power and sometimes not.  Power change variances ranged from -.7hp to +3hp.  In most cases the effect was to simply move the existing power up the power curve, closer to red line.  For all practical purposes, in the real world, such changes are in drivability, not quarter mile times.  Straight line seat of the pants improvements would for all practicle puposes be undetectable, except in mind of the rider where the change in decible levels and power curves might be erroniously interpreted as noticably more power.  Additionally, differences in rider expertise, would no doubt offset any actual power differences.

The primary benefit was in weight loss, where there was always a loss in system weight.  I don't have the weight differencial figures.  But, I'm thinking it maxed out around 10 lbs.

So, in the best case scenario, for somewhere between $600.00 and $1200.00, you gain 3 hp and loose 10 lbs.  Is it worth it?  Not for me.  But for some young people, with all the wisdom that implies, bragging rights and "look at me" are worth every penny. 
Title: Re: Open Exhaust...?
Post by: kwells on May 16, 2008, 09:47:58 PM
For my Sprint, the pipe was 375.00 and I lost about 14lbs of weight.  It is louder than stock but I likes it that way.  It adds a very modest 3-4HP max to my chart. Some mapping changes gives the torque curve back its straight profile.
A pipe on a modern day bike without mapping changes does nothing except save weight.  Some of these systems by the way will weigh in at over 30lbs stock.  There is significant savings to be had on them especially with the stock dual catalytic converter systems.

BTW the Vision system weighs 29lbs.  That is massive for such a small bike.
Title: Re: Open Exhaust...?
Post by: Rick G on May 16, 2008, 11:42:38 PM
If you want to get a little more sound from the stock exhaust, drill 6 1/4 inch holes around the exhaust outlet
in a circular configuration . It will warm it up a little bit and get away from the whoosh sound of the stock pipes.
Title: Re: Open Exhaust...?
Post by: Walt_M. on May 17, 2008, 05:48:10 AM
Loud exhausts also have the benefit of attracting the attention of those fine folks with the flashy red and blue lights on their cars.
Title: Re: Open Exhaust...?
Post by: kwells on May 17, 2008, 01:08:56 PM
Personally If I wanted to sink into the shadows I'd probably stay home.  Red and Blue tends to find me regardless of my pipes.
Title: Re: Open Exhaust...?
Post by: Walt_M. on May 17, 2008, 01:33:10 PM
What I meant was, on the occasion when I want to let her rip I don't want the law to hear me a half mile away and come looking. If I am careless and they see me, ok, my bad. My bike has Spec IIs and I do keep the packing fresh, it is pretty loud if I don't.
Title: Re: Open Exhaust...?
Post by: Coil Coyle on May 17, 2008, 11:57:48 PM
Quote from: Walt_M. on May 17, 2008, 05:48:10 AM
Loud exhausts also have the benefit of attracting the attention of those fine folks with the flashy red and blue lights on their cars.

My "pull over quick; be non-threatening and polite" method of dealing with officers doesn't work as well when you have loud pipes.

$0.02
;)
Coil
Title: Re: Open Exhaust...?
Post by: inanecathode on May 18, 2008, 12:32:58 AM
Quote from: coilXZcoyle on May 17, 2008, 11:57:48 PM
Quote from: Walt_M. on May 17, 2008, 05:48:10 AM
Loud exhausts also have the benefit of attracting the attention of those fine folks with the flashy red and blue lights on their cars.

My "pull over quick; be non-threatening and polite" method of dealing with officers doesn't work as well when you have loud pipes.

$0.02
;)
Coil

Or ape hangers for that matter.
Title: Re: Open Exhaust...?
Post by: macroars on May 18, 2008, 05:47:58 AM
Quote from: Rick G on May 16, 2008, 11:42:38 PM
If you want to get a little more sound from the stock exhaust, drill 6 1/4 inch holes around the exhaust outlet
in a circular configuration . It will warm it up a little bit and get away from the whoosh sound of the stock pipes.

I did that:
http://web.mac.com/roarstokken/RoarS/Media/Original%20pipes.wav (http://web.mac.com/roarstokken/RoarS/Media/Original%20pipes.wav)
http://web.mac.com/roarstokken/RoarS/Media/Drilled%20pipes.wav (http://web.mac.com/roarstokken/RoarS/Media/Drilled%20pipes.wav)

I really liked the "new" sound!

In addition I had a more rational reason - I patched a hole, and wanted to reduce the pressure inside the mufflers to make it last longer....
Title: Re: Open Exhaust...?
Post by: reardeac on May 18, 2008, 04:03:18 PM
acee,
what do you plan on doing with your old exhaust is it in decent condition. i also am of the school of thought that quiet pipes keep your butt from getting a ticket, especially here in the burg that i live in. i would gladly by it if it isnt rusted through anywhere. i love the balanced look of an exhaust on each side of the bike but no way am i buying predators.
thanks
Title: Re: Open Exhaust...?
Post by: vadasz1 on May 18, 2008, 06:50:55 PM
Drilled - definately sounds better to me.

Somewhat loud pipes are alright as motorists will definately know you are near them on the highway.
Title: Re: Open Exhaust...?
Post by: acee125 on May 18, 2008, 07:26:25 PM
reardeac,

Assuming I like my Mac's once I get them. I will probably sell them.
Title: Re: Open Exhaust...?
Post by: Brian Moffet on May 18, 2008, 07:29:48 PM
Quote from: vadasz1 on May 18, 2008, 06:50:55 PM
motorists will definately know you are near them on the highway.

Well, they'll know you're in front of them.  Loud pipes don't do much if you're behind someone...

Brian
Title: Re: Open Exhaust...?
Post by: Walt_M. on May 18, 2008, 08:13:41 PM
All this 'loud pipes' talk is assuming all the other drivers in all the other vehicles around you can hear or don't have their sound systems cranked up so loud they can't hear anything else. Anyone's best defense is to be as aware as possible of their own surroundings. How is that possible if the only thing you can hear is your own vehicle?
Title: Re: Open Exhaust...?
Post by: reardeac on May 18, 2008, 08:18:21 PM
one of my other rides is a ural. the transmission is full of square cut gears that crunch every time i shift.... it sends cold chills down the spines of everyone near. the ural riders have a saying..... loud gears save lives
Title: Re: Open Exhaust...?
Post by: Walt_M. on May 18, 2008, 08:24:59 PM
Ok, if you ride a Ural you may not be run over by a pedestrian while you are shifting gears!
Title: Re: Open Exhaust...?
Post by: reardeac on May 18, 2008, 08:34:46 PM
i had a mb unimog and wasnt any less likely to be the victim of stupid drivers than on a bike. the best offense is good defense
Title: Re: Open Exhaust...?
Post by: h2olawyer on May 18, 2008, 09:50:04 PM
Like the dealer told me the day I bought my Vision -- "There are two types of drivers on the road, those that don't see you & those that are aiming for you."  Sage advice.

H2O
Title: Re: Open Exhaust...?
Post by: macroars on May 19, 2008, 01:11:10 AM
My mc-teacher repeated several times during the driving lessons: to live long, you ought to understand those driving cars as dumb, blind and deaf.
Title: Re: Open Exhaust...?
Post by: h2olawyer on May 19, 2008, 01:31:23 AM
Quote from: macroars on May 19, 2008, 01:11:10 AM
My mc-teacher repeated several times during the driving lessons: to live long, you ought to understand those driving cars as dumb, blind and deaf.

But I'll bet they play a mean pinball.   ;D

H2O
Title: Re: Open Exhaust...?
Post by: Tiger on May 19, 2008, 06:59:07 AM
Quote from: h2olawyer on May 19, 2008, 01:31:23 AM
Quote from: macroars on May 19, 2008, 01:11:10 AM
My mc-teacher repeated several times during the driving lessons: to live long, you ought to understand those driving cars as dumb, blind and deaf.

But I'll bet they play a mean pinball.   ;D

H2O

;) but they need "a suple wriiiiiiist"... ;)
Title: Re: Open Exhaust...?
Post by: YellowJacket! on May 19, 2008, 09:28:51 AM
I don't think loud pipes make much difference to people in cars...just the ones out of them.  For instance, many new cars...especially luxury cars, have so much sound deadening crap in them that you  cant hear a bomb go off.  Add inthe high end noise cancellling sound systems a cell phone, latte, and three screaming kids and you still have a recipie for disaster.  Teenagers intheir cars with loud stereos (youn inattentive drivers) are not going to hear loud pipes.  And even me, in my 2002 accord, can't hear them until they pass me.
This phenomenon is why many fire/rescue/police departments are having so much trouble.  I don't play my music loud and can't hear an ambulance until it is right on me.

David
Title: Re: Open Exhaust...?
Post by: Brian Moffet on May 19, 2008, 12:43:20 PM
Quote from: YellowJacket! on May 19, 2008, 09:28:51 AM
This phenomenon is why many fire/rescue/police departments are having so much trouble.  I don't play my music loud and can't hear an ambulance until it is right on me.

And ambulances, fire-trucks, police cars have their sirens facing forward, not just back like an exhaust pipe would be.

Brian
Title: Re: Open Exhaust...?
Post by: acee125 on May 19, 2008, 01:26:26 PM
Good point! I also rarely hear a police car, fire truck, or medical vehicle until they are right on top of me.
Title: Re: Open Exhaust...?
Post by: h2olawyer on May 19, 2008, 03:16:05 PM
That's why I drive a cage with the same scanning I use on the bike.  Check all rear view mirrors often - at least once every 15 seconds.  I like to know where everyone around me is.  In most situations, the emergency vehicle won't catch you that quickly, giving you time to get over to the edge of the road to let them pass.

Around here, the law is to pull over as far as possible & come to a stop to let the emergency vehicle pass.  When I moved here in the late 80s, it was like the parting of the Red Sea.  Traffic in BOTH DIRECTIONS would pull over & stop.  Today, I often see traffic continuing at or over the speed limit, in the left lane, forcing the emergency vehicles into the turn lanes (if available) or into the oncoming lane to get past them.   ::)

With today's technology, maybe they could start putting a small receiver in each car to give the driver a warning that emergency vehicles are approaching from the rear or side.  Just a thought.

H2O
Title: Re: Open Exhaust...?
Post by: Lucky on May 19, 2008, 05:13:05 PM
Quote from: h2olawyer on May 19, 2008, 03:16:05 PMWith today's technology, maybe they could start putting a small receiver in each car to give the driver a warning that emergency vehicles are approaching from the rear or side.  Just a thought.

H2O

they have one already, although it's organic not electronic, it's called "My Wife" ! :D
Title: Re: Open Exhaust...?
Post by: h2olawyer on May 19, 2008, 05:20:55 PM
The main problem with organic warning devices is that they can be one of the biggest driving distractions as well.

H2O
Title: Re: Open Exhaust...?
Post by: inanecathode on May 19, 2008, 11:04:48 PM
Bigger crash bars on fire trucks should do it.
Speaking of, whats most annoying is if you're on a divided highway or street, and theres an ambulance coming down the oppisite lane of traffic (remember now, big concrete wall between the sides of the highway) everyone on my side pulls over.
Really. Whats the ambulance going to do? Jump the barrier? Toss out an EMT with a parachute into our side of the highway? Really, i'm curious.
Title: Re: Open Exhaust...?
Post by: kwells on May 19, 2008, 11:15:02 PM
CO drivers in general lack common sense.  They will actually nearly cause accidents instead of simply slow down and be aware.

Title: Re: Open Exhaust...?
Post by: Rick G on May 20, 2008, 05:42:43 PM
Maybe some kind of radio controlled ejection seat . If you don't pull over , you get shot through the roof of your car!