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posted January 29, 2002 07:50 PM
Doug, swft, y2k, kcadby, others... opinions please! The topic about the 12R throttle body boots (inside the airbox) has come up again at LAB.
Though many are claiming that they are getting ready to do this "mod", to the best of my knowledge, TedG and maybe Vincent Hill, are the only two that have done this. I'm not in anyway doubting Ted's results, but I was wondering if any of you have experimented with this and were there any measurable positive (or negative) results from it?
Since I am not any kind of engineer, nor do I have much of a clue concerning flow densities, vortices and the like, I'm just curious if there is any benefit from this. In your "opinions", of course. The reason I'm asking is that I'm in a position to easily perform this modification. Though Ted's logic on this appears to be reasonable, I'm under the belief that there is a lot more involved in the dynamics of the air flow from the snorkle's intake to the combustion chamber. To alter or vary one aspect could easily have an effect on the components of the "air flow equation".
This could have a positive affect (i.e. Ted's 213 mph indicated), but I'm concerned that it could equally have a negative affect in speeds below, say... 150 mph. My thinking on this is that if it was the "restriction", it would have required a lot more engineering then just a couple of guys saying, "Hmmmm... let's just choke off the air to the throttle bodies by restricting the incoming air. Ooooooh, I'd figure reducing the opening's diameter, say 2~2.5 mm oughta do it." Possible? Yes? Likely? I'm not so sure on that one.
On the other hand, it could possible explain why the A/F ratios tend to be on the rich side, wouldn't it? As for being the "restriction" everyone has wondered about, I don't really care. I have little to no interest in doing 200+ mph. I DO have interest in improving my bike's overall performance... especially when there is little to no cost involve. So, is it worth the time and effort or is it kinda pointless unless I plan on going to Bonneville or Maxton?
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There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
posted January 29, 2002 08:43 PM
I don't know if my results were because of the boots, but I do know I lost no drivability that I could perceive. I do know that now on a cool day my bike power wheelies when I crack it wide open, when it didn't do it before. Big deal you say!! Try to do that at 5000 feet. I don't think the boots helped that but cutting them but didn't hurt. Here it is in a nutshell, the only way to really find out is to have a cut set and a stock set, and go make top end runs with each. The dyno may or may not show much because there is no ram air effect. But I do know what a restrictor plate looks like and those lips look like a NASCAR restrictor plate to me. If it were done for reversions they would not encircle the boot they would be segmented usually 4 thin square patches, probably no more than 1mm thick. I believe the GXSR 1000 uses the patches. There would be no advantage to midrange power using the lip all the way around, all that it would do is cause vortices, causing turbulance, and that causes drag, which slows down the air velocity. This is not a day and night fix, but it seems to hit the revlimiter harder in the higher gears.
____________
Ted
2000 Green ZX12 sold
The fast color!!
Green 2005 ZX10R
2009 Concours Black ABS
posted January 29, 2002 08:46 PM
Also think of a cheaper easier way to restrict only the top end of the bike.
____________
Ted
2000 Green ZX12 sold
The fast color!!
Green 2005 ZX10R
2009 Concours Black ABS
posted January 29, 2002 08:59 PM
This would be the most practical way to restrict them. Look what they did in France.... This is how they restricted them there. Why wouldn't they do the same here just not as much?????? Anyone have a picture of the lip your are removing I may give it a go....... Thanxxx All...
Needs a life
Full throttle!
Posts: One MEEEEEELLION
posted January 29, 2002 09:00 PM
I couldn't say what the design intent was, but Mike Velasco smoothed everything out in the intake tract when he built it.
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82 Gpz750, 84 Ninja 900, 2000 ZX12R (Muzzy Big Bore Kit), *another* 2000 ZX12R (Muzzy custom stroke crank 1341cc motor), 2004 ZZR1200, 2005 ZX10R, 2007 ZX14, 2008 Concours 14, 2014 Versys 650, 2014 Yamaha WR450F, 2015 Ninja H2
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posted January 29, 2002 10:02 PM
Edited By: redelk on 29 Jan 2002 22:30
Please don't take offense, Ted I don't want to appear that I was questioning your results. Even though I spend some time above 10K RPMs, the majority of my time is spent bouncing around the 5K~9K area. I do mean BOUNCING! On any given ride, I'll spend 90% of a 200+ mile ride and not see a straight away longer the a 1/4 mile and they will usually end with a sharp 15~25 MPH curve. Quite often, it will be followed by another one going in the opposite direction.
So you see, a constant 5K power wheelie is not always in my best interest. You'd think that after almost 2 years and over 28K miles, I would have learned better throttle control, eh?
Seriously though, I only see altitudes higher the 1500 ft., when I go to the Gap. Most of the time, I'm under 1000 ft. I'm currently using DaveInDaytona's map, since our modifications are very similar. I'm still "struggling" with it. Though our dyno runs on the same dyno are fairly close (his was 180 vs. mine at 177), it has had a radical effect on my bike's overall response to throttle input. It seems that everytime I go over a small rise and upshift, I look like I'm qualifying for the Isle of Man.
Having the front wheel float up is one thing, but when both wheels completly loose contact with the good ole terra firma, that's a whole new ball game. In other words, I could personally care less if my bike is capable of 180, 190 or even 200... MPH or RWHP. Odds (and the size of my balls) are greatly against me seeing an actual 190 (about 208 on my bike's speedo).
Also, I have yet been even close to having any kind of "control" of the HP available to me now. I guess what I'm trying to say is that I'm on that quest of "smooth and predictable" power delivery and throttle response.
I recently rode a box stock GSXR 1000 and marveled over it's smooth power. There was plenty of power to get me from curve 1 to curve 2 and it was smooth enough to keep me outta trouble coming out of the apex of curve 2. Especially when I whacked it's throttle with my customary ham fist.
I guess what it is that I don't want a "light switch" response where it goes from "1" to "11" with very little (or NOTHING) in between. I also have no plans on keeping the throttle pinned for any measurable amount of time. It's bad enough with it's "warp speed" accelleration.
I'm also concerned on what kind of affect it will have on the engine braking. This is a very important tool to me and the way I ride (too slow!). It might not alter it at all. Admittedly, not having done the mod myself, I couldn't answer that. No offense, but with the altitude differences between us, as well as the slight difference in our riding preferences, I'm just curious if this would be a benefit for where and how I ride.
I'm also wondering what kind of changes (if any) would I need to make on my current map to take full advantage of this mod. I'm hoping to install my halmeter from NE Dyno this weekend. That is after my welder fixes the gaping hole currently in my Ti header. I gave him a threaded bung made out of "black metal" instead of something like stainless steel. Needless to say, it didn't work. On the bright side, both the "hole" and the "fix" won't cost me anything. They're my customer.
Unlike Y2K's timing mod or the oil pressure mod, once this mod is done to the intake boots, there is no going back. Due to rescent and unexpected financial difficulties, my interest in "do it yourself" mods have really gone up. Still, so has my level of caution. Knowing that any "mistake" I make it the "fabrication" or disappointment in it's results, well be something I'll have to deal with for a while.
I'm sure that if I made a "mistake" or wasn't happy, those boots probably don't cost that much. The thing is, it will be taking money that I could have used for something else. Again, I'm not trying to "diss ya" in any way. Just please forgive my paranoia. When someone says "It couldn't hurt", for me, it actually could. In more ways then one.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
posted January 29, 2002 10:06 PM
can someone post a picture of what your talking about Im very interested but I guess dumb right now??
MM
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200-MPH CLUB MEMBER!
posted January 29, 2002 11:57 PM
2001 boots... Another thing to add here is that Kawasaki apparently changed these boots on the 2001 model. I think they made them a smaller diameter to increase velocity. It could be that because of the 186 mph limit on the '01, they didn't need the larger size anymore. -ZXtra
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The sixth sick sheik's sixth sheep's sick!
posted January 30, 2002 01:47 AM
Edited By: kcadby on 30 Jan 2002 14:26
Dammitt...RedElk...I've just GOT to learn to read faster!?!?!?
I posted this over there before I saw this thread...
It's simple to see...
I have one in my hand right now...wish I could post a picture...IMAGESTATIONSUCKS...
Take the access covers off...take the 2 bolts out of the "duct"...pull the duct out and turn it around so that the SMALL END is staring you in the face...You are now looking right at the line that was made by the throttle body being larger than the duct...
What bothers me more than this duct/throttle body size difference is the fact that every ZX12 I've seen has the ducts "rippled" from being compressed (sort of like standing on beer/soda can)...
When the 2 bolts are tightened...it pushes the duct into the throttle body making it seal better but...it also compresses the duct itself making it ripple, which CAN'T be good for optimum air flow...even on a stock motor...
I LOVED the aluminum "velocity stacks" (AKA ducts)...that South Africa BEAR made for his bike and wish they were available to everyone that wanted them...I would have put them on AT LEAST 4 bikes by now...
I'm thinking about "trying" to get these ducts I have off this 1361 motor I'm building "straighter" but it WON'T be easy...since they're rubber (flexible)...
DOUG??? (Spencer)
MIKE??? (MaxV)
I think they would sell IF you made them???
The hardest part about making them would be...how to seal them to in the air box...
BEAR's picture weren't good enough for me to see how he sealed them in the air box...maybe he didn't???
I will add this here...
I think that IF Kaw really did restrict these bikes??? (I don't REALLY think they did)...they would have to make the ducts WAY smaller than they did...
LOOK at how small the restrictors are in the picture above What speed is THAT bike restricted to???
If the SMALL lip on our intakes is enough to "restrict" us...it would SEEM that the above pictured bike would run what??? 50MPH!?!?!?
I just don't think the lip in question will make THAT much difference...
That being said...
I CAN'T STAND TO SEE INDUCTION PARTS THAT DON'T "FIT RIGHT"...EVERY LITTLE BIT HELPS!!!
FIX/FIT THEM!!! I DO...
posted January 30, 2002 07:21 AM
A short answer is that as far as pressure testing on a flow bench, the % of airflow difference is tiny, and it would be very difficult on a dyno to measure a HP gain.
Its difficult enough to get repeatability on dynos without changing anything. The way a dyno is used is a bigger varriance than 1 or 2 hp.
As far as air flow, every little bit adds up. If you matched the stacks to the throttle bodies and the manifolds to the head and blended the valve throat and the seats and tweaked the chamber to the seat and the chamber to the cylinder wall etc. then you may get some noticeable gains.
After doing all the above and taking pressure readings on a SF flow bench I picked up a few % of air flow, testing at 10" of test pressure.
I dont have my notes handy but If I remember correctly the intake at .310" lift flows 128 cfm at 10" test pressure. And the exhaust was 87.5% of the intake. Thats a very nice ratio.
Turbulance... thats another factor. Turbulance is like frame flex. Ideally you want to control it but not totally eliminate it, not that you could eliminate it. Basically without getting into Kaos and the art of predicting un predictable flow predictions, (if that makes any sence), you want to reduce turbulance in the port. Thinning the boundry layer is just like enlarging the port. However, the boundry layer has functions. One function, and its bigest is it helps keep the fuel from touching the port wall and "droping out". On the port floor this is especially important. Some times turbulance is induced in ports to keep the fuel drop out to a minimum. Its sometimes done with casting texture or dimpling much like a golf ball. Sometimes a vane is used on the port floor. At low port velocities a vane in affect makes the air think its in a smaller port while at higher velocities the trailing air (cone behind the vane) shortens behind the vane and velocity is reduced as if the cross sectional area of the port was enlarged.
AS far as the stack to throttle body mismatch? The only time I've seen an annular turbulance ring used is on exhaust ports to reduce reversion. But in that case the diameter is reduced using a cone type ring. In this case this is more of a step to a larger diameter. Could it be for reversion? Or maybe they wanted a velocity change at that point. As in smaller diameter stacks to improve low speed driveability? Maybe its just a manufacturing compromise? I dont really have an answer why its there but kawi either didnt feal it was a problem or it was an oversight. I dont personally thing its "the restriction" that kawi is rumored to have built into the bike.
If there is any restriction that was done to the bike in the days just prior to production it would be in the software in the eeprom in the ECU.
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Y2KZX12R
CompetitionCNC.com
posted January 30, 2002 08:10 AM
Edited By: zx12richard on 30 Jan 2002 08:11
Hey guy a free place to post pics is still available...
http://communities.msn.com/ You set up your own community and post fromit.... VERY easy to do just takes a couple of minutes. The downside is 3MB. But set up Multiple acounts such as ZX12richard,zx12richard1, and so on. I really would like to see them boot pics..... I am very interested in this subject. To me it makes sence as when they detuned in France this is where they started...... So who knows but we need to find out...... Thanxxx all.....
posted January 30, 2002 08:39 AM
My .02 I think that smoothing the transition between the subject parts is just good engine building and anyone would be a slacker not to do it. I think that the mismatch is the result of production tolerances and simply a small instance of something that could have been done better but wasn't. I think that the impact on top speed might be on the order of less than .5 mph (if that), and the impact on peak numbers on the dyno might be on the order of 1 hp max assuming that the mapping is done to corrrect for the increased airflow, if any......
Doug
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It's not that I think you're dumb, it's just that so much of what you know isn't true....
posted January 30, 2002 10:36 AM
Redelk none taken I am convinced this is what they did to take the edge off. Even more so when I see the French bikes. That is just my opinion, take it or leave it. Y2K thinks differently and he knows more about flow than I do(and I respect what he says). I am just repeating what I have found. My results are seat of the pants, and uncontrolled conditions top end runs. So I may be full of it(as we all know I am). But I'll bet I'm not. Like I said, take it or leave it, It's just my opinion.
____________
Ted
2000 Green ZX12 sold
The fast color!!
Green 2005 ZX10R
2009 Concours Black ABS
posted January 30, 2002 10:43 AM
Does anyone have a pic of the lips... I seen it once wished I saved it... I want to see how easy to do it without tearing mine apart today... LOL I think EVERY little thing helps...
posted January 30, 2002 12:46 PM
My eyes don't see that good I can't see the lip in the pics..... But I pulled mine out this morning and looked.... Whats the best way to cut it out.... You can feel it better than you can see it....
posted January 30, 2002 01:44 PM
I thought by now (most) people had accepted the fact that there was no edge to be taken off.
Doug
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It's not that I think you're dumb, it's just that so much of what you know isn't true....
posted January 30, 2002 06:30 PM
Hp I think if you buy 200 shares of Microsoft on friday after 10:30 am and hold for 60 days you could pay to have a motor built that would have more Hp than you can use !
posted January 31, 2002 04:51 AM
Anyone can buy someone elses HP.
I enjoy working on bikes as much as riding them.
Its nice now thats its a hobby again. Doing it every day takes some of the fun out of working on your own stuff.
Having someone else build an engine for me would be like having someone else ride the bike for me.
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posted January 31, 2002 10:53 AM
Can't cut what's not there... I inspected mine and even removed them. I can't find or feel any discernible lip. At best, there might be a lip of LESS then 1 mm. There is a slight "dimple" about 4 mm from the edge, but running my finger over the point where the rubber ends and the throat of the TB starts, there really isn't any difference.
This makes me think that it's just a poor tolerance from the factory. Like Doug and others have said, it doesn't hurt to have a smooth transition between the two pieces, but I don't think that this "lip" was designed into the bike. In other words, I could see the size of these lips being different from bike to bike.
I have taken some crappy pics (I didn't take off the tank), it's just that I have no where to post them. They basically shows a smooth transition between the two pieces. Any cutting I did could easily cause more problems then solve. With a lip of less then 1 mm, if I did cut, it could expose the edge of the throttle body and just create more turblance.
____________
There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.
-Ernest Hemingway
posted January 31, 2002 01:14 PM
I'm with redelk on this. I've got an early 2000 12, and there is no discernable edge between the stack and throttle body - certainly nothing anywhere near 2.5 mm.
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posted January 29, 2002 07:50 PM
posted January 29, 2002 08:23 PM
Edited By: 
posted January 29, 2002 11:57 PM
-ZXtra
What speed is THAT bike restricted to???
posted January 30, 2002 06:30 PM
