Secondary Butterflies

[gPink]

What do you find smooth about being hard on the throttle and waiting for power delivery? We're not talking about a 200 hp motogp bike with peaky power spikes that need to be electronically controlled. I found the secondaries unpredictable and sometimes upsetting.

[tomp]

I found the secondaries unpredictable and sometimes upsetting.

I believe that is the crux of all this.  It's the "I found. . ."  A personal expectation vs experience, that varies with every rider.  I find the 14's acceleration linear and experience what I expected.  You, on the other hand didn't experience what you expected for/from a 1400cc bike.  Having never been a supersport rider, I wasn't wanting or expecting that level of response from the 14.  As it is, I can out run most vehicles I come in contact with, excluding ZX14's etc, and I'm ok with that.   You wanted more, and the Guhl/ plate removals will give you more of what  YOU expected.  At least mods were available to improve upon what you had.   A win-win for all, as I see it...   

Conniesaki, it's threads like this that make the interweb interesting.  This and possibly sites sometimes labeled XXX...tp

[Steve in Sunny Fla]

On my previous post I mentioned they don't restrict unless at WOT. What I meant is at WOT, they restrict some,

[xxx] It's painfully obvious they restrict power at lower rpms and not  even at low rpm WOT . I pointed out the power gains flashes and fly removal make. if the flies weren't  restricting flow, there WOULD BE NO GAINS.

  And I don't do this often, but I know carburetion better than anyone here, and if you know me you know I'm not a braggart. I can read what's happening by turning the throttle and feeling what happens. I can use widebands for final tuning, but trust me, I get fueling even in old school form.  That said, I've tuned carbs with cv's for what, 3 decades, I have developed a control system for the slides that I was warned "would ruin my carbs" just as I outran the naysayers...[xxx]

   and still, it's all about just what the secondaries are doing, everyone is still ignoring the other variable...vvt.  Steve

[tomp]

Looks like this discussion has been around other bike forums for quite a while now.  More to add to the confusion. . .

http://www.r3owners.net/threads/secondary-butterfly-questions.221/

Here's one from Infinity owners.  Seems they wonder about them too... Don't we have some Infinity owners here?  I used to have one. 
http://www.nicoclub.com/archives/ca18det-secondary-butterflies-control-system.html

And here's what the Sport Rider Magazine Geek says about them. 

http://www.sportrider.com/tech/suzuki-bandit-secondary-butterflies-and-oversized-tires-ask-geek

[Steve in Sunny Fla]

 OK, read the last link Tomp provided, what suzuki says about their secondaries. I have never seen that - ever. yet read it, it's the same thing I have already written in this thread. Steve


"The official word from Suzuki is that its SDTV (Suzuki Dual Throttle Valve) system brings superb response feel, smooth power delivery, improved mileage and reduced emissions. The secondary butterflies do this by opening just enough to provide the optimum intake velocity based on throttle position and rpm rather than letting you decide with your throttle inputs. For example, if you were to open the throttle fully at low rpm on a setup without the secondary butterflies, intake velocity would drop and the engine would not pull cleanly. In addition, the secondary butterflies can smooth the off/on response by opening at a set rateagain, no matter how quickly you open the throttle. And as we’re finding out with more bikes in recent years, in some cases the secondary butterflies are used to restrict the engine’s output to meet emissions requirements."

[MAN OF BLUES]

   and still, it's all about just what the secondaries are doing, everyone is still ignoring the other variable...vvt.  Steve

[xxx]funny, nobody, and I mean Nobody... fully understands VVT, and it's co-ordination with Ram-Air induction[xxx]

[maxtog]

Jim locked the thread for a while, giving some time for people to reflect and for some needed cleanup.  Please remember while we might not all agree with each other, keep the postings focused on the topic but without drifting to insults or personal attacks.

This is a great thread with lots of postings containing valuable questions, speculations, theories, links, information, and even some facts too!  It is up to you to decide which category each falls into.  Hopefully with time and analysis some type of accurate, overall picture will form about the ever mysterious and interesting secondary butterflies and we will all be better for the experience 

I am unlocking it now....  Stand back... this posting will self-destruct (in a while, anyway)

[maxtog]

Looks like this discussion has been around other bike forums for quite a while now.  More to add to the confusion. . . [links]

That is some good info, especially the last link on Sport Rider providing stuff from Suzuki (which Steve quoted, above)

[just gone]

OK, read the last link Tomp provided, what suzuki says about their secondaries. I have never seen that - ever. yet read it, it's the same thing I have already written in this thread. Steve


"The official word from Suzuki is that its SDTV (Suzuki Dual Throttle Valve) system brings superb response feel, smooth power delivery, improved mileage and reduced emissions. The secondary butterflies do this by opening just enough to provide the optimum intake velocity based on throttle position and rpm rather than letting you decide with your throttle inputs. For example, if you were to open the throttle fully at low rpm on a setup without the secondary butterflies, intake velocity would drop and the engine would not pull cleanly. In addition, the secondary butterflies can smooth the off/on response by opening at a set rateagain, no matter how quickly you open the throttle. And as we’re finding out with more bikes in recent years, in some cases the secondary butterflies are used to restrict the engine’s output to meet emissions requirements."

Steve, it may not make any difference to your point, but I think the only words in that paragraph that may have actually came from Suzuki are the ones I highlighted in blue. The rest appears to be the interpretation of same and further input by the author (Andrew Trevitt)? I've only searched for a few minutes, but in that short time I was unable to find any official word from a Suzuki website that associates Suzuki Dual Throttle Valve with reduced emissions. I'll keep searching.

[Steve in Sunny Fla]

Ok, since we're back in business, i do want to give a shout out to Rembrant - I feel he is actually the most knowledgeable on the secondary's action on this thread, and he has personally played with the maps and graciously provided them for us. That's not speculation folks, that's fact, which is what we sorely need. Thanks Rem - Steve

[Rembrant]

Ok, since we're back in business, i do want to give a shout out to Rembrant - I feel he is actually the most knowledgeable on the secondary's action on this thread, and he has personally played with the maps and graciously provided them for us. That's not speculation folks, that's fact, which is what we sorely need. Thanks Rem - Steve

LOL...well, the way I see it, either you're interested in this stuff, or you're not.
It's interesting to me to see what the bike's controls are trying to do.

In discussing what the secondary flies primary purpose is, it is interesting to note that they did do semi-gear specific mapping for them...maps for gears 1-2, 3-4, and 5-6. By comparison, the fueling and ignition are a bit simpler...one fuel map for all gears, and one ignition map for all gears. On the second gen bikes, the ECO mode utilizes slightly different fueling and ignition maps...but the secondary fly maps are all the same if I recall correctly. The ECO mode looks to be about 5% leaner on the fueling and uses about 2 degrees more ignition advance.

In looking at the secondary fly maps, you can clearly see the progression of the flies from closed to open. The map is relatively easy to change...you just have to make sure you keep it smooth and not make massive number jumps imho. The other big thing is not to open them too early...it could be simply unsettling, and it could be downright dangerous. I think this is one area where fly removal is more beneficial than reprogramming them.

It wouldn't hurt to talk to Turbo (Mike) in TN...I believe he bought the Woolich kit for his track built ZX10R, and was going to for the C14 as well...he was going to experiment with a ported and polished C14 cylinder head, and possibly ZX14 pistons to boost compression?...My memory is gettin' fuzzy on the topic now.

[B.D.F.]

Each of the maps for the secondaries opens them earlier / farther in the higher gears; first map is conservative (gears 1&2), second map is a bit more aggressive, opening the 'flies sooner (3 &4) and finally the most aggressive of all the maps is for 5&6. Exactly the way you would expect if the goal is to tame the bike's output.

The interesting trial would be to just open the 'flies all the way whenever the bike was running; that would simulate the 'flies being removed. The problem is the fast idle cam comes into play and the engine will not idle.

Brian

LOL...well, the way I see it, either you're interested in this stuff, or you're not.
It's interesting to me to see what the bike's controls are trying to do.

In discussing what the secondary flies primary purpose is, it is interesting to note that they did do semi-gear specific mapping for them...maps for gears 1-2, 3-4, and 5-6. By comparison, the fueling and ignition are a bit simpler...one fuel map for all gears, and one ignition map for all gears. On the second gen bikes, the ECO mode utilizes slightly different fueling and ignition maps...but the secondary fly maps are all the same if I recall correctly. The ECO mode looks to be about 5% leaner on the fueling and uses about 2 degrees more ignition advance.

In looking at the secondary fly maps, you can clearly see the progression of the flies from closed to open. The map is relatively easy to change...you just have to make sure you keep it smooth and not make massive number jumps imho. The other big thing is not to open them too early...it could be simply unsettling, and it could be downright dangerous. I think this is one area where fly removal is more beneficial than reprogramming them.

It wouldn't hurt to talk to Turbo (Mike) in TN...I believe he bought the Woolich kit for his track built ZX10R, and was going to for the C14 as well...he was going to experiment with a ported and polished C14 cylinder head, and possibly ZX14 pistons to boost compression?...My memory is gettin' fuzzy on the topic now.

[Rembrant]

Each of the maps for the secondaries opens them earlier / farther in the higher gears; first map is conservative (gears 1&2), second map is a bit more aggressive, opening the 'flies sooner (3 &4) and finally the most aggressive of all the maps is for 5&6. Exactly the way you would expect if the goal is to tame the bike's output.

The interesting trial would be to just open the 'flies all the way whenever the bike was running; that would simulate the 'flies being removed. The problem is the fast idle cam comes into play and the engine will not idle.

Brian

Yessir, I'm with you on all counts. My involvement in this whole discussion was more with the how, and less with the why. It was always my understanding that the flies were there to tame the bike's output.

Somebody mentioned earlier that the flies were there to smooth the power delivery, and make the 1400 power plant less radical as it were...but I can't say I agree with that myself. I had a PC3 and flies removed on my 08 C14, and that bike was smooth as glass and it ran like a champ.

I'm only here for the technical discussions anyway...my C14 is currently all stock, at least with regards to fuel, air, and exhaust;).

Rem

[Gigantor]

Yessir, I'm with you on all counts. My involvement in this whole discussion was more with the how, and less with the why. It was always my understanding that the flies were there to tame the bike's output.

Somebody mentioned earlier that the flies were there to smooth the power delivery, and make the 1400 power plant less radical as it were...but I can't say I agree with that myself. I had a PC3 and flies removed on my 08 C14, and that bike was smooth as glass and it ran like a champ.

I'm only here for the technical discussions anyway...my C14 is currently all stock, at least with regards to fuel, air, and exhaust;).

Rem

Rem,

Maybe you can tell me why tuners get more power with the secondaries in?

[Rembrant]

Rem,

Maybe you can tell me why tuners get more power with the secondaries in?

Can you tell me what or where the more power is that you're referring to?

I have no idea if I can answer that question or not...

I know that in the case of the ZX14R, they're now leaving the flies in (but reflashed via the ECU) Annnnd adding a piggy-back PC5 for fine tuning...

[Deziner]

I know that in the case of the ZX14R, they're now leaving the flies in (but reflashed via the ECU) Annnnd adding a piggy-back PC5 for fine tuning...

^^^ Smart!  Tunability of the secondaries AND fuel trim! Plus an auto tune 

[B.D.F.]

The only reason I can see to leave them in would be because they can or will be opened all the way and therefore not relevant.

Again, the secondary throttle plates are just another set of throttle plates, in- line in the induction system, just before the throttle plates the rider controls (with the right twist grip). Closing them will have the same effect as closing the throttle.....  which begs the question, how much do I close the throttle to get maximum power. <chuckle> The next question is if restricting the intakes produces more power, why are the throttle bodies on a ZX 14 larger in diameter but otherwise identical to the C-14? Does anyone really believe that smaller intakes result in more power, all else being equal? And finally, if the C-14 gains power by having smaller or restricted intake tract size, why does replacing the smaller throttle bodies on the C-14 with the larger throttle bodies of a ZX 14 increase the power output of a C-14? There is a gentleman here who in fact has an 08' C-14 with ZX (larger) throttle bodies on it, no secondary plates ('flies) and it has been dyno'd at 168 Hp. I know the person who owned the bike, did the swap and tuned it saw the bike 'in the flesh' so to speak.

1) The Earth is not flt.
2) That bright thing in the sky is not Apollo the Sun god riding his fire chariot.
3) Reducing the induction system on an air pump (which is what an I.C. engine is) does not increase its effective displacement, all else being equal.

 

Brian

Can you tell me what or where the more power is that you're referring to?

I have no idea if I can answer that question or not...

I know that in the case of the ZX14R, they're now leaving the flies in (but reflashed via the ECU) Annnnd adding a piggy-back PC5 for fine tuning...

[elp_jc]

For those who think they're smarter than a team of dedicated powertrain engineers, the secondary flies are there for a legitimate reason, or manufacturers wouldn't have spent the money and R&D to incorporate them. Same thing if it was safer to add power by advancing timing, and crap like that 'flashing' does. You can do any of that, but ALWAYS AT A COST.

As far as why larger diameter TBs, they increase power up top, but affect mid-range torque and rideability. It's not just about power and/or torque. It's HOW IT'S DELIVERED in the entire rev range. Yes, sometimes higher velocity (restricted) intake air produces smoother and/or higher torque, especially at partial throttle. Without throttle-by-wire, you need a secondary set of ECU-controlled butterflies to achieve that. What's going on here is some folks want to alter the nature of a sport-touring bike by making it a sport one. Nothing wrong with that, but every such change has consequences, even if they don't know which ones . Have a good one.

[Daytona_Mike]

Interesting thread. I find it interesting that those who do not or have not experienced 'flies out' have strong opinions.
Me, I have files out and a full area P. There is not one single detriment in doing so . (I dont have traction control and dont want it either.)
I have ridden many stock C14's and they are ok  but do not come close to how well this bike delivers great power when ever  and where ever I want it. It will never be a ZX14 that is true but that is it not what I was trying to do.
I dynoed at 161.3 and I have gotten 52 miles to the gallon and top out at 170 indicated. Where is the problem?
If I bought a new  C14 the very first thing I would do is do the same thing as I have now.  Make the engine run better and get rid of the stock suspension.
Am I smarter than a bunch of engineers? Of course not.  I do not have to be. I only have to be smart enough to know what to do thanks to the great folks here on this site. Obviously  I now  know what to do.

[Rembrant]

Interesting thread. I find it interesting that those who do not or have not experienced 'flies out' have strong opinions.

Bingo.

It is a bit unfortunate that ever since the whole C14 ECU flashing began, that the secondary fly removal somehow became obsolete or "insufficient", archaic, etc.

Originally, the secondary fly removal and the additional of the tried and true PCIII was THE mod, and not once, not ever, did anybody ever complain or comment that it didn't improve the bike immensely. The same cannot be said about the ECU flashes.

I've had an 08 C14 with flies removed, exhaust, and a PCIII with Fuel Moto tune, and I now have a 2010 c14 that I've tried every way possible...PC5 with autotune and flies out, custom autotuned ECU with flies in, etc, etc. I know exactly how they all work, and I've always maintained that my 08 with flies out was the best way the C14 worked, and I rode that bike coast to coast.

I'm not saying that a C14 with a flashed ECU/flies IN doesn't work well...because they do work well, it's just that IMHO, they do work better with a PC and flies out. That's my own view on the matter, and it can be taken with a grain of salt.

Rem