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Cool. Then I'll save money and be content with what I already have. TA is awesome. If the Sparks is identical then good job.

Thanks! Your in good shape with what you have.
 

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Well said Tom. Now I'm pulling that head off my Trx480 cause I don't want to be part of any haters !

You got a extra head laying around ? Lol
Moi...was the gain with the Sparks pipe just on top? How did the Sparks megaphone pipe's curve compare to the Dasa from 5000 RPM to the limiter? Was it a consistent 2hp gain across the board, or did the Sparks line cross the Dasa's at some point?
 

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Moi...was the gain with the Sparks pipe just on top? How did the Sparks megaphone pipe's curve compare to the Dasa from 5000 RPM to the limiter? Was it a consistent 2hp gain across the board, or did the Sparks line cross the Dasa's at some point?

Our 2hp gain was across the whole powerband. Oh yeah and the 2tq!
 

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Moi...was the gain with the Sparks pipe just on top? How did the Sparks megaphone pipe's curve compare to the Dasa from 5000 RPM to the limiter? Was it a consistent 2hp gain across the board, or did the Sparks line cross the Dasa's at some point?
It was mostly on top end. I would give more info but I didn't print the graph :unsure:
 

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thats a badass lookin exhaust..
 

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ok i have a real question lol this is probably gonna sound dumb but would this exhaust be any good on a mx bike or a track bike or is it mainly focused toward drag racing bikes ? and by mx bike i mean a mild build like stage 2 cams, crank, 13.5-1 piston, that sorta stuff
 

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The explosion that occurs in the cylinder during combustion is processed through the exhaust valves and into the header as a actual flame. To define flame travel to those that don't know, it is the exhaust gases exiting the head, the hotter the gas (flame) the faster it travels through the header, maintaining this flame is key. The flame can be extinguished or prolonged based on the size of the header in relationship to the build size. Flame travel is key in maintaining power, if the flame cools too quickly while traveling through the header substantial power loss will occur. The prototype 3 step headers were targeted towards 575+cc motors which require more air flow through the header and can maintain flame travel longer with increased header diameters. These larger diameters can be an advantage in big cc motors as long as the steps are positioned correctly. The production exhaust have an advantage over the original prototypes in that they will work with a broader range of builds, maintain the flame travel longer, while releasing into a larger megaphone which is where the power advantages are produced over the competition.
Exhaust System

http://speedtalk.com/forum/viewtopic.php?f=15&t=18687&start=90 : Science and Implementation of High Performance Exhaust Systems



Explosion in the cylinder? Uncontrolled burn?

Scratching head...
 

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The explosion that occurs in the cylinder during combustion is processed through the exhaust valves and into the header as a actual flame. To define flame travel to those that don't know, it is the exhaust gases exiting the head, the hotter the gas (flame) the faster it travels through the header, maintaining this flame is key. The flame can be extinguished or prolonged based on the size of the header in relationship to the build size. Flame travel is key in maintaining power, if the flame cools too quickly while traveling through the header substantial power loss will occur. The prototype 3 step headers were targeted towards 575+cc motors which require more air flow through the header and can maintain flame travel longer with increased header diameters. These larger diameters can be an advantage in big cc motors as long as the steps are positioned correctly. The production exhaust have an advantage over the original prototypes in that they will work with a broader range of builds, maintain the flame travel longer, while releasing into a larger megaphone which is where the power advantages are produced over the competition.
This really can't be left uncorrected, as other people might end up here looking for exhaust system information and see this. Rocksalt's links above are helpful and so is this: http://www.profblairandassociates.com/pdfs/Back_to_basics.pdf

A high-pressure compression wave travelling at the speed of sound is what Tom is confusing with a "flame". The speed of sound increases with temperature, and thus the time required for the acoustic wave to reach the end of a given duct length increases with temperature by the same relationship. Duct diameter also changes the medium through which the acoustic wave travels--some literature states that smaller diameters will tune more sharply (and detrimentally at high engine speed), and larger diameters will decrease the strength of acoustic tuning.

It is not the compression wave's travel to the end of the tuned length (the muffler) that matters as much as the returned suction wave's travel back to the exhaust valves. When an exhaust system is tuned correctly for a desired engine speed range, the suction wave that is returned by the compression wave reaching the open duct end will arrive at the exhaust valves during overlap to decrease cylinder (combustion chamber) pressure. This scavenges residuals (exhaust particles) and helps suck in more intake charge shortly after intake valve opening. Both lead to increased power and torque production. It's a similar goal as in 2-stroke exhaust tuning, but the goal there is to bring positive pressure back to the exhaust port to cram scavenged charge back into the cylinder. Here we're trying to pull a vacuum on the exhaust valves before they close.

A reverse cone megaphone allows the returned scavenging wave to arrive the exhaust valves in overlap over a broadened engine speed range. In the tuning sense, it is less "peaky" than a straight pipe. If a perfectly tuned straight headpipe created a great torque peak at 8000 rpm, a reverse cone megaphone system tuned for the same speed might make the same peak torque but torque past the peak will be up, especially past peak power (overrev). While the engine speed has risen too high for the straight headpipe to return a properly timed suction wave to the valves (duct needs to be shortened), the megaphone system will still be doing its job due to its broadened tuning characteristic.

What creates the broadened tuning of a megaphone system? The best explanation I've heard is that the wave reflection occurs in the divergent cone rather than at a straight duct's acoustic end. The geometrical discontinuity of a straight duct end to atmosphere is an infinite area ratio and would return a very strong negative pressure wave over a short period of time. When the wave reflection occurs in the cone, the suction wave becomes longer, with some amplitude sacrificed to achieve this. Reverse cones contribute further to this, as megaphones without them have been known to be peaky.
 

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Alright guys - no one is getting banned - but lets try to get a few things straight.

First, no matter which side of the fence you're on, let's keep the personal attacks out of the forum - period. I don't care who has wronged you in the past or how many times they've wronged you, swallow your pride and be the bigger person.

No one wants wants the drama. An ATV forum isn't the place to create it or look for it.

No one wants to read arrogant or negative posts. Everyone involved in the flame fest that follows negative posts just end up looking ridiculous.

Everyone involved in the drama ends up perpetuating the hate towards one side or the other to insure negative/arrogant/combative posts occur in future.

Let's keep it simple. If you like MX, XC, Duning, Dragging, or just riding around your house - it doesn't matter. If you like stock engines, endurance engines, or high dollar engines - it doesn't matter. We're all on the same team - we all love riding quads.

If you have something to add to a thread - keep it civil, positive, and informative. That's it. You don't need to call someone an idiot if they post something incorrect. And for anyone else flaming a negative post - two negative posts DO NOT make a positive post.

I've cleaned up this thread and deleted several posts because I'd like to keep the thread open. Doesn't matter if you agree, disagree, or are indifferent with that method, it is what it is. Again, let's stick with posts that are constructive, helpful, and productive.
 

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Mornin,i saw this thread & I have a quick question for quad racers,do you know what would be the smallest build you could put this pipe on? For example I have an 0/7 er with a ported head,14-1 piston(stock bore)cam,carbuerator work & pro design air filter,vortex ignition & a-market pipe,I was told it made about 53 h.p. From the guy I bought it from.is that something I could run now with jetting adjustment?when it's time to rebuild this motor My goal is to get around 60 h.p. it's primarily a duner & I was almost sure that I was going to buy a dasa until I saw this thread,thx
 

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Mornin,i saw this thread & I have a quick question for quad racers,do you know what would be the smallest build you could put this pipe on? For example I have an 0/7 er with a ported head,14-1 piston(stock bore)cam,carbuerator work & pro design air filter,vortex ignition & a-market pipe,I was told it made about 53 h.p. From the guy I bought it from.is that something I could run now with jetting adjustment?when it's time to rebuild this motor My goal is to get around 60 h.p. it's primarily a duner & I was almost sure that I was going to buy a dasa until I saw this thread,thx
This pipe is designed to work with 575cc engines and larger, meaning in the range of 80hp plus based on the necessary airflow. There are many other better and cost effective exhaust choices for a 60hp engine that will make more efficient and a more broad power curve. In comparison, I would not expect this megaphone pipe to make anymore power up top than a shorty Dasa on such a mild build, yet I would expect low end power to suffer because of the backpressure loss from the larger pipe diameter and core size.
 

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10-4 thx for the explanation I appreciate it.so do you think I should wait until I know exactly the build & parts I'm going to use to decide if I get the dasa regular or shorty? Also I was planning on getting a fuel custom intake & ditching the stock air boot & pro design filter & running those two until it's time to deal with the rebuild.maybe I could get some help from the members on adjusting the jetting or run my quad up to dasa for a Dyno tune,thx
 

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Doubt I’m going to get a response. But do you guys recommend me running this pipe. I am running on a sb/ss motor. It’s fully built by sparks. I have the oldest model pipe. It sounds and looks great but the inside is falling apart from many years at the oceano dunes. I love sparks. Best in the business in my opinion. My quad pulls really hard. It surprises many people with how quick it is. I have the sparks 13.5.1 high compression piston, sparks valve spring kit, sparks clutch, dynatek programmable Cdi, bored fcr carb, clean up port(which I plan on getting ported to a drag port), and stage 2 hot cams(which I plan on getting a more aggressive cam with extended valves. I’m not 100% sure but my butt dyno is guessing anywhere from 60-65 hp. When I rode at the dunes I would beat all my buddies, dasa 480 with some racers adge porting, another sparks built 450r, 520 yfz on nos. I had a 400 with one of the megaphone pipes and loved the power increase. I really love the look and power of these pipes. I’m going to be needing a new pipe soon so I really need to know if I could run this pipe and how I can get one.
 

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152023
152024

Here’s my bike and photo of me talking home the trophy. Was only behind cause they jumped and I wanted to wheelie.
 
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