Custom Exhaust Installed
- Thread starter freponyryd
- Start date
homdai
Registered
+1
This is totally the right approach, let the guy alone, his bike, his call.
And I also agree on the HP loss but still, if he's like me, not running track or anything, he won't miss few HP's anyway.
Not digging the pipes myself, but he did'em himself, some credit for that guys.
My 2 cents.
freponyryd
Registered
I did some more work on them and tucked them in closer to the swingarm, like some (all) of you suggested, and it does look better, thanks for the input. As far as slash cutting them you'll just have to get over that one. I like them and I think they don't really look that bad they kind of blend in with the swing arm and they have an awesome sound. And these will do until I get the money for a set of Micron's or the Vance and Hines the other guy posted on here a few days ago, in which someone said they looked like a mid evil blacksmith made them, maybe he hasn't seen mine yet. Someone really should refer him to this thread.
And as far as the power loss issue, please explain to me how if it loses power it might "feel" and "seem" faster when in all actuality it is slower? Now I realize I am not an exhaust designer or a rocket scientist and this was just a rough draft if you will, but that doesn't make any sense. A flow through pipe is after all a flow through pipe. How many chambers does the R77 have hidden inside? If none, then there is no difference except a perforated inner tube possibly back filled with steel wool or some other fiberous weave creating a silencing effect by trapping some of the passing gases like a silencer on a firearm. I would really appreciate someone with some debatable knowledge on this subject to explain in detail the how's and why's. If your just coming here to flame me because you don't like the pipes I made and you just want to poke a little fun you'd be better off to keep your comments to yourself. I believe everything negative that can be said or implied already has been and at this point its kind of like kicking a dead horse and you are just making yourself look like an *******. So to recap anyone with real knowledge on the subject I would really appreciate the input.
Thanks,
And as far as the power loss issue, please explain to me how if it loses power it might "feel" and "seem" faster when in all actuality it is slower? Now I realize I am not an exhaust designer or a rocket scientist and this was just a rough draft if you will, but that doesn't make any sense. A flow through pipe is after all a flow through pipe. How many chambers does the R77 have hidden inside? If none, then there is no difference except a perforated inner tube possibly back filled with steel wool or some other fiberous weave creating a silencing effect by trapping some of the passing gases like a silencer on a firearm. I would really appreciate someone with some debatable knowledge on this subject to explain in detail the how's and why's. If your just coming here to flame me because you don't like the pipes I made and you just want to poke a little fun you'd be better off to keep your comments to yourself. I believe everything negative that can be said or implied already has been and at this point its kind of like kicking a dead horse and you are just making yourself look like an *******. So to recap anyone with real knowledge on the subject I would really appreciate the input.
Thanks,
seat of the pant power increases are very often more "sonic" increases in power..
Meaning, you think you are faster because of the noise you are making.. not at all uncommon.. This was often the case in the days of carburetor motors and guys putting air cleaner lids upside down or open elements.. They thought they were going faster when in fact, they lost power..
You can not tell the difference in a couple horsepower by the seat of the pants when you are dealing with a 1-3% change, just not possible... (I can prove this on the race track and have)
Did you loose power? could be, can you tell for sure? nope.. the comment "less back pressure means more power" is certainly laughable at any rate..
The drag bike guys can vouch for this big time... A couple years ago, the Kawasaki guys all raced big megaphone pipes when some guy shows up and starts running a tenth or 2 faster than everyone else out of the blue..
One savy racer happened to look deep into the megaphone and found a pipe (restriction) had been added.. the net increase was substantial enough to give this guy a most certain advantage in heads up racing... within 2 weeks, everyone had the same pipe..
Torque curves typically suffer a major hit when back pressures are not maintained..
IMO, on a street machine, total power really is not the issue as you spend so little time "on the throttle" anyway. Response is much more important than "total Power" and in that respect, sometimes quiet can be a lot faster..
If you like being conspicuous (you are the loud bike of the group) then more power to you, I personally like to "romp" the bike without all the attention myself... I know of a couple bikes that run weekly and simply take the cans off the bike while racing..
Meaning, you think you are faster because of the noise you are making.. not at all uncommon.. This was often the case in the days of carburetor motors and guys putting air cleaner lids upside down or open elements.. They thought they were going faster when in fact, they lost power..
You can not tell the difference in a couple horsepower by the seat of the pants when you are dealing with a 1-3% change, just not possible... (I can prove this on the race track and have)
Did you loose power? could be, can you tell for sure? nope.. the comment "less back pressure means more power" is certainly laughable at any rate..
The drag bike guys can vouch for this big time... A couple years ago, the Kawasaki guys all raced big megaphone pipes when some guy shows up and starts running a tenth or 2 faster than everyone else out of the blue..
One savy racer happened to look deep into the megaphone and found a pipe (restriction) had been added.. the net increase was substantial enough to give this guy a most certain advantage in heads up racing... within 2 weeks, everyone had the same pipe..
Torque curves typically suffer a major hit when back pressures are not maintained..
IMO, on a street machine, total power really is not the issue as you spend so little time "on the throttle" anyway. Response is much more important than "total Power" and in that respect, sometimes quiet can be a lot faster..
If you like being conspicuous (you are the loud bike of the group) then more power to you, I personally like to "romp" the bike without all the attention myself... I know of a couple bikes that run weekly and simply take the cans off the bike while racing..
freponyryd
Registered
Now that makes sense, but like I said in the first post I did put restricters inside the pipe. Granted I'm no matmatician and did not figure out the total cfm before and after. I did however run the straight pipes without the restricters and I did find that it did feel a bit slower, but I then made and installed the restricters and it feels different (ie. more powerfull than without)
/-----------------------
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in out
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Not sure if that helps, but the overall inner dimension of the exit pipe has only changed by .25 inch.
Besides it was just something to play around with for the time being. I dont know that I will leave them on there more than another week or so, I just wanted to see if I could make something that sounded cool and shaved some weight off. And in my opinion I have suceeded.
/-----------------------
--------/ -------/
in out
--------\ -------\
\-----------------------
Not sure if that helps, but the overall inner dimension of the exit pipe has only changed by .25 inch.
Besides it was just something to play around with for the time being. I dont know that I will leave them on there more than another week or so, I just wanted to see if I could make something that sounded cool and shaved some weight off. And in my opinion I have suceeded.
+100 I am SO with you on that. All I could do was shake my head in disbelief.
10SS, Check your facts, dude, seriously.
In my personal experience, anything done to reduce back-pressure or increase flow after the collector is free horsepower assuming the fuel curve is there. All engine/exhaust combinations have dips & peaks in the power curve resulting from that particular combination of primary tube diameter & length as well as collector size & length. As most of you already know, the first consideration header builders design for is for max flow in the primary tubes - they have to be big enough to eliminate restriction while maintaining the velocity needed for scavaging as much burnt gas as possible. If only that was all you had to worry about. Turns out the exiting gas also creates a pressure wave that turns around when it reaches the "end" of the pipe and heads back toward the engine. When it gets back to the engine it disrupts/slows the velocity of the still exiting gas and cause a dip in the torque/power curve. A "tuned" exhaust is one where pipe diameter & length is adjusted so this happens (hopefully) at a point in the power band away from the needed power curve, as well as achieving maximum scavaging where most needed. Anti-reversion lips, stepped primaries, coatings to keep heat in and velocity up, are all part of the arsenal used to get that last horsepower. Builders' these days use sophisticated computer programs that consider all this in relation to intake-cam-head flow before spitting out design parameters.
I mention all this because 98% of this happens before the end of the header collector. On a stock bike, almost every consideration after that point is meant to meet noise laws (or pollution laws in the case of the catalytic converter). Increasing flow at the can by reducing back pressure can add a few horsepower without significantly impacting any of the header design characteristics, but may creat a lean situation at some RPM's that require additional fuel. Virtually every a/m can has significantly less back pressure and more flow than most stock systems. Interestly, one of the reasons the 2008 exhaust is so huge is to try to quell the noise without adding unneeded back pressure. But if you don't care about noise,achieving this gets a lot easier.
A racing exhaust can be a significantly different animal since it's designed from the start for max power at high RPMs. In some racing exhausts, a portion of the midpipe & canister is actually an extension of the header collector. The circumferance and length of the collector dramatically impact peaks/dips in the power curve, but this doesn't really apply to the stock exhaust the same way it does to a 4 into 1 or a 4:2 racing exhaust. Look at Brock's exhausts to illustrate an example, You can get his 4 into 1 header with A/H, meg, or std canister with similiar power but requiring somewhat different maps. The point being that even on those hi-po systems the canister has a lot less to do with power output than the header design. Also consider the 1/2 dozen a/m systems where you can insert plugs or additional baffling to reduce the noise. None of them claim to increase power by adding a flow restrictor which increases back pressure. Although some do claim not to lose much.
There is a difference between the design parameters of a stock exhaust and a racing exhaust. One may react differently than the other to the same modification or change. Pure science aside, sometime's it cool to just try something different.
I mention all this because 98% of this happens before the end of the header collector. On a stock bike, almost every consideration after that point is meant to meet noise laws (or pollution laws in the case of the catalytic converter). Increasing flow at the can by reducing back pressure can add a few horsepower without significantly impacting any of the header design characteristics, but may creat a lean situation at some RPM's that require additional fuel. Virtually every a/m can has significantly less back pressure and more flow than most stock systems. Interestly, one of the reasons the 2008 exhaust is so huge is to try to quell the noise without adding unneeded back pressure. But if you don't care about noise,achieving this gets a lot easier.
A racing exhaust can be a significantly different animal since it's designed from the start for max power at high RPMs. In some racing exhausts, a portion of the midpipe & canister is actually an extension of the header collector. The circumferance and length of the collector dramatically impact peaks/dips in the power curve, but this doesn't really apply to the stock exhaust the same way it does to a 4 into 1 or a 4:2 racing exhaust. Look at Brock's exhausts to illustrate an example, You can get his 4 into 1 header with A/H, meg, or std canister with similiar power but requiring somewhat different maps. The point being that even on those hi-po systems the canister has a lot less to do with power output than the header design. Also consider the 1/2 dozen a/m systems where you can insert plugs or additional baffling to reduce the noise. None of them claim to increase power by adding a flow restrictor which increases back pressure. Although some do claim not to lose much.
There is a difference between the design parameters of a stock exhaust and a racing exhaust. One may react differently than the other to the same modification or change. Pure science aside, sometime's it cool to just try something different.
2Wheels2Live
Registered
+1. A for effort but I don't think they work well with the bike. Shorter, tucked in tighter, flared out abit in diameter and slash cut I think would help a lot
BowDown
Registered
Wow another cherry bomb installation! This time on a Gen II.
I do have to mention that I was the first!
http://media.putfile.com/Hayabusa-Cherry-Bomb-Exhaust-Video
Crap, they removed my video...
I do have to mention that I was the first!
http://media.putfile.com/Hayabusa-Cherry-Bomb-Exhaust-Video
Crap, they removed my video...
Last edited:
Need pix of the modded pipes and yes you removed the youtube vid. Don't know how I missed this thread. It's your ride enjoy it 
2Wheels2Live
Registered
Wow another cherry bomb installation! This time on a Gen II.
I do have to mention that I was the first!
Funny Videos, Funny Pictures, Flash Games, Jokes
Crap, they removed my video...
this grave dig gets a big ole'
VANNWRAY
Registered
well spoken as everything i've read from your posts , don't care for the length but i sure like the color . Good on you for fabricating your own piece of art .you can always play and tune . We used to paint our race car exhaust and cut the exhaust and 1 1/2 past the burn mark . Might be worth your time . Good luck with it . No need for the hate , he was asking for opinions to start with .
freponyryd
Registered
here is the big girl now.
dude I wouldn't let anything negative said get you down this is the harshest reaction I've seen on the org though. Anyhow do your thing regardless that's kinda the point and they really didn't look that bad. Although not quite my thing either I wouldn't knock ya for it.
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