Secondary Butterflies removal review

I could see if you were only racing wide open all the time now if that is not the case then I believe they should stay on just to kepp it meaning air/fuel correctly. Why are they there has anyone asked suzuki? When you are at full throttle they are wide open unless you are bogged down then they may correct the air/fuel flow? Any of you have a data logger on your bike to see what you are doing to it when removing them?
 
Amode said:
Really Frank
2%, 5%, 10%, !5%, 20%, 40%, 60%, 100%. Sounds like the Numbers game. I like this. If your on the dyno why would you tune at these numbers. I have been tunning motors since you were probbally in three cornerd pants. Pro stock, Blown gas, top fuel. 2%, 5%.:whistle:
Click to expand...

The throttle percentages I stated were for a powercommander, as an example. In ECU editor, you would again tune at different throttle percentages (9,11,16,21, etc.) versus rpm . . the point being that tuning isn't just done at WOT thereby making dynos useless, because you can never get it right, as you said originally. On carbed bikes it would main, needle and bottom end, much less precise than fuel injection, but tuning would again occur at less than WOT.

As far as you tuning since I've been in diapers, I have well over 35 years tuning, so you can whistle all you want grandpa, I'm probably old enough to be your older brother!:rofl:

Anyway, lets not jack this thread about removing butterflies with this, what I will say is that I still think the Busa head flows well enough to remove the butterflies. And with proper tuning, you will see big improvements all over.
 
sixpack577 said:
How bout everybody back up and read the original few posts on this thread?...
...There is much more bottom end power available SOONER with them gone, regardless that it's not as smooth, and maybe a little slower. I'm not claiming my seat of the pants can tell you it's more powerful. I'm saying that it lifts the front much easier! They're in there for emmisions, and to smooth the power delivery. To make the bike more usuable and rider friendly, for the folks that just bought a Busa to cruise, or at least not get the most out of it.
Funny how critics haven't tried it, and don't realize what the original point of the mod was.
Click to expand...

the purpose behind having secondary throttle plates is not for emissions. they control the amount of air flow entering the engine based on load, atmospheric conditions, and engine speed.
by keeping the secondary throttle plates closed at lower engine speeds you are making the air enter the engine at a higher speed than it would be if the intake tract was wide open.
higher air (speed)velocity = more torque and power at low-mid engine speeds. which is where your bike gets all its wheelie power.
they open up fully when approaching peak hp so the air volume(quantity) is increased.
kind of like turning the water hose on full blast and putting your thumb over the end. the water is coming out at a higher speed. this is velocity. when you remove your thumb you get a higher volume of water, but it's moving slower.
more velocity makes higher low end/mid range power. (torque/wheelie power)
more volume makes higher top end and peak power.

removing the secondary throttle plates on a stock engine with no other mods isnt giving your engine any more power or bringing peak power on sooner. its slowing the air speed entering the engine down thus having a negative affect on low end output.
having the STP in is not going to affect peak hp anyways because the bike can only flow so much volume in the first place.
its all about intake tuning.
research variable length intake manifold. THIS is the same concept.

maybe if you were to tune the bike to compensate for your changes could you see an improvement. and of course changing displacement, cams or the way the head flows would also affect this. but that still doesnt change the fact that you dont need large volume of air at lower engine speeds.

AGAIN, if i am wrong, please correct me!
 
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A couple observations about this thread.

1 - The guys against removing the secondaries have not tried to remove it, they have a sound theory on why the STP is there but have not tried removing it because the theory is strong, therefore they are convinced. I was all for the air flow theory too (until I tried my bike without the secondaries).

2 - The guys who tried (including myself) share the same opinion, the throttle response has improved VERY significantly (feels a lot more touchy, like a 1000) and it feels like there is more power available sooner (not more power, the same but available sooner, rendering wheelies easier). I myself have dynoed it before and after and found negligible differences in peak power or power curve on a 4th gear pull at the dyno - only felt more crispness at the throttle and felt more power available sooner in lower gears. This is not mental, this is very sensible. I am no strange to my bike and can tell what kind fuel I have for 5 hp power differences, no placebo effects on the throttle response and higher grunt down low.

If we are all following logics here, isn´t real world evidence from more than one people enough for it to get at least a shot from other people before settling for an opinion? We are talking a reversible mod here that is not very complex...

One can find many plausible explanations for the STP, including performance increase in lower RPMs or emissions - none of the possible explanations, except emissions, would explain why the manufacturer would include something on a product they claim to be the fastest bike in the world that would hurt performance.

They would only do it if they HAD TO, along with the need to add the new feature for selectable power delivery mode.

All I know is I cant help but notice every single time I WOT it that the bike feels so much better at lower RPMs.

I would even say I would accept having lost power if it was the drawback for the newfound throttle response I have now.
 
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bradbusa said:
the purpose behind having secondary throttle plates is not for emissions. they control the amount of air flow entering the engine based on load, atmospheric conditions, and engine speed.
by keeping the secondary throttle plates closed at lower engine speeds you are making the air enter the engine at a higher speed than it would be if the intake tract was wide open.
higher air (speed)velocity = more torque and power at low-mid engine speeds. which is where your bike gets all its wheelie power.
they open up fully when approaching peak hp so the air volume(quantity) is increased.
kind of like turning the water hose on full blast and putting your thumb over the end. the water is coming out at a higher speed. this is velocity. when you remove your thumb you get a higher volume of water, but it's moving slower.
more velocity makes higher low end/mid range power. (torque/wheelie power)
more volume makes higher top end and peak power.

removing the secondary throttle plates on a stock engine with no other mods isnt giving your engine any more power or bringing peak power on sooner. its slowing the air speed entering the engine down thus having a negative affect on low end output.
having the STP in is not going to affect peak hp anyways because the bike can only flow so much volume in the first place.
its all about intake tuning.
research variable length intake manifold. THIS is the same concept.

maybe if you were to tune the bike to compensate for your changes could you see an improvement. and of course changing displacement, cams or the way the head flows would also affect this. but that still doesnt change the fact that you dont need large volume of air at lower engine speeds.

AGAIN, if i am wrong, please correct me!
Click to expand...

I can't argue that what you say makes sense, except for one thing.
It wheelies much easier now with them out! I didn't have a problem wheelieing with them in, but with them out, it's a night and day difference.
Folks will argue all day that you can't use your "seat of the pants dyno" and I would agree. But this isn't saying "Oh, it's so much faster now", but simply, when I hit it in 1st or 2nd, it lifts faster and easier. To any who doubt this, prove me wrong.
I would also bet that with a good tune, the bike runs no worse with them out, maybe even a little better.
Dozer reminds a good point too, that they are there for ABC modes too.
They are also in ALL years of the GSXR 1000s, without the mode selector, as well as several other makes and models. I still belive they are there for street friendly driveability for the masses. They help keep the front wheel down on hard acceleration.
 
jeepinocala said:
I could see if you were only racing wide open all the time now if that is not the case then I believe they should stay on just to kepp it meaning air/fuel correctly. Why are they there has anyone asked suzuki? When you are at full throttle they are wide open unless you are bogged down then they may correct the air/fuel flow? Any of you have a data logger on your bike to see what you are doing to it when removing them?
Click to expand...

My bike runs, sounds, and smells fine:laugh: and the spark plugs look great. The engine has not been leaned out. Could it benefit from a new fuel map? Absoloutely. I gutted my convertor too(it cooked my feet, not trying to gain power) The bike can be slightly sluggish at certain rpm's. And I noticed this after doing each mod seperatly. Eventually I will have the money for all the mods I want, and a proper tune for them.
In the meantime, I'm happy with it, it serves MY purpose...keepin it on one wheel. And just to stir the pot, I honestly think it runs stronger on top speed runs. The engine seems like it breathes better and buries the needle much faster. But that's just my seat of the pants meter:laugh: The wheelie thing is legit.
 
sixpack577 said:
My bike runs, sounds, and smells fine:laugh: and the spark plugs look great. The engine has not been leaned out. Could it benefit from a new fuel map? Absoloutely. I gutted my convertor too(it cooked my feet, not trying to gain power) The bike can be slightly sluggish at certain rpm's. And I noticed this after doing each mod seperatly. Eventually I will have the money for all the mods I want, and a proper tune for them.
In the meantime, I'm happy with it, it serves MY purpose...keepin it on one wheel. And just to stir the pot, I honestly think it runs stronger on top speed runs. The engine seems like it breathes better and buries the needle much faster. But that's just my seat of the pants meter:laugh: The wheelie thing is legit.
Click to expand...

Same feeling here.
 
sixpack577 said:
:beerchug: I've seen your video, you'de be suprised how many folks have never run theses things wide open.
As well as alot of smart folks who would rather crunch numbers than just try a 10 minute mod. Oh well.
Click to expand...

My point exactly its a free easily reversible mod but all the benchracers want to piss and moan about it. If you have a gen 2 or a B-King give it a try if you don't care for it change it back no harm done.
:banghead:
 
I would like to try this today just to see what it does. My gut feeling however is that it will have a negative affect on low end grunt for the reasons stated above.
In my mind I can't think of any other reason for them being there, if not to help INCREASE bottom end power delivery.
Yes I agree they can be used to restrict power (as seen in s-dms) but I don't feel that's the case in "A" mode. I think they're there to keep the bike from falling on it's face when you wanna stomp it at lower rpms.
I'll post up my results later today :beerchug:
 
bradbusa said:
I would like to try this today just to see what it does. My gut feeling however is that it will have a negative affect on low end grunt for the reasons stated above.
In my mind I can't think of any other reason for them being there, if not to help INCREASE bottom end power delivery.
Yes I agree they can be used to restrict power (as seen in s-dms) but I don't feel that's the case in "A" mode. I think they're there to keep the bike from falling on it's face when you wanna stomp it at lower rpms.
I'll post up my results later today :beerchug:
Click to expand...

I heard ECU editor can adjust the position of these flies... has anyone played with that?
 
POWERHOUSE said:
We have, and it does work. I am still a fan of the butterflies removed . . .
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have you seen power gains or sooner power delivery on a stock or otherwise un-modified 2nd gen busa?

i definitely think one could benefit when accompanied with other mods.. just seems like these are there to control air velocity at lower engine speeds.

i really hope i dont come off sounding argumentative on here. that is not my intention by any means.
in trade school they preach the velocity/volume and other intake tuning theories, so this is where i'm coming from..
 
Try it! Run your bike as fast and hard as you can in 1st and 2nd. Then do some wide open roll ons from 6k to 8k at a slow cruising speed. Now repeat without the secondaries. Tell me you don't notice a big difference, you don't even have to look for it, it's unquestionably right there in your face. Proof enough to me that with the right tune, it would be an even bigger improvement...for certain folks and riding styles.
 
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lol if i ran full throttle in 1st id be laying on my back.. im only about 145 pounds.
2nd gear stays down but gets real light on me at wot. i didnt get to tear into it today, some friends came into town and this is my only transportation, so will have to try it when i get a free minute.
 
I suggest, to whoever tries the bike without them, to rev halfway through the course of the throttle, let it back for a sec and then twist it again all the way through.

In stock trim the bike wheelies if you do that, no secret there, but the difference in power delivery will be felt instantly. Second gear wheelies too if you WOT it right after first.
 
I will be your huckleberry :laugh:, going to do this mod when I put in a new air filter, if I like it, then I'll do the king too, hell what's there to lose by trying something new
 
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