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This was posted over on Bikeland today, with no attribution to it's origin (yet):





This would be killer if accurate, but without knowing the original source, it's kinda hard to put much credibility to it at the moment....

Still, we can dream.... graph looks pretty good, doesn't it? Though 113 ft-lbs of torque isn't going to help rear treadlife.... :angry
 

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Kinda hard to place credibility in the dyno chart when like Warchild said you don't know the source. Numbers on the chart don't look quite right, and here is MHO on it.

Torque X Engine Speed divided by 5252 equals HP. Kawasaki gives a figure of 113.5 lb/ft of torque at 7500 RPM for the ZX14. Using the formula, that works out to 162 horsepower. Looking at what supposedly is a dyno chart from the GTR1400, it shows 113.47 lb/ft of torque at what appears to be 6750 RPM and horsepower is 159.41. Plugging the numbers into the formula gives a HP of 145.8 HP.

So, until the source of the chart is revealed, hard to say whether it is true or not. I guess we will have to wait and see!
 

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As others have said, if this is real this is a perfect powerband for a sport touring bike. 100 lb/ft of torque from 5,000-9,000rpm.

If Kawi is claiming 113.5 lb/ft of torque you can bet that that is cranksahft readings. Wheel readings would be down about 15% with the efficiancy losses of a shaft final drive.
 

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You are correct concerning the HP formula and again correct at 145.8, however that would be at peak torque. If you use what appears to be 100lb/ft at 9000 rpm you get 171HP. That number is probably high and dosen't really match what we see on the graph...my guess is a bad graph. Although with the electronic wizardy now available I suppose its possible they could tone her down on the top end through cam/spark & fuel control.
 

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So now that the torque (100.3 lb/ft) and engine speed (6200 rpm) have been released.... the above formula equals 118.40 HP. That seems low to me. :rant
 

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If you use what appears to be 100lb/ft at 9000 rpm you get 171HP. That number is probably high and dosen't really match what we see on the graph...my guess is a bad graph.
The graph does in fact have an error, but that doesn't mean that the essence of the information contained therein, is incorrect. To the contrary, the graph contains information that agrees significantly with the peak torque number that appears on the Kawasaki USA web site.

The error is revealed by the fact that, as "fossil mel" points out, whenever torque is expressed in English units of lb-ft (or more correctly, lbf-ft), if you multiply the torque by the rotational speed in rpm, and then divide by 5252, you get the power in hp. Consequently, whenever these English units of measure are used on a dyno chart, and the same numerical scale is used for both torque and power, the two curves must cross at 5252 rpm. On this chart, the two curves cross at around 5800 rpm, suggesting that the numerical value of the torque is too great relative to the numerical value of the power.

This error appears to be consistent throughout the graph. I don't have a clue as to the cause of the error, but I have seen this sort of error appearing on other dynamometer charts, and when this sort of error is present, it does not render the graph invalid. Rather, the error suggests only that the calculation of torque from power contains a computational error. (Dynojet uses an inertial dynamometer if I recall correctly, in which case torque would very likely be calculated from power, in contrast with brake dynamometers, where power is calculated from torque.)

The power at 6200 rpm agrees exactly with the peak torque number that Kawasaki USA published on their Web site. Kawasaki reported that the peak torque is 100.3 lb-ft at 6200 rpm. As 08CC14 points out, the power at 6200 rpm, according to Kawasaki USA, is thus 118.4 hp. If you look at the power curve on the graph, at 6200 rpm, it agrees exactly. The graph does show the torque peak to be at about 6800 rpm instead of 6200 as Kawasaki reported officially, but that isn't significant, because the torque curve is practically ruler flat between 6000 and 7800 rpm. The unusually flat shape of the torque curve also lends support to the legitimacy of this graph. I am inclined not to dismiss this graph, and I am greatly encouraged by the prospect of having in excess of 150 hp from 8000 to 9600 rpm!
 

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:crazyloco Thanks for the explaination!:mfclap So as I interpret that well thought out bit of wisdom... if my little brain serves me correctly... even though there is only 118 HP at peak torque of 6200 RPM... that does not necessarily mean max HP... which in reality is not achieved until reaching nearly 9,000 RPM at which time Connie will purr out 159.41 HP as delivered... leaving yet a few ponies in the barn to be gingerly coaked and released after applying a few aftermarket remedies by said lesser engineer minded CC14 owners. Thanks! :rofl
 

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only 118 HP at peak torque of 6200 RPM... that does not necessarily mean max HP... which in reality is not achieved until reaching nearly 9,000 RPM
Well of course. My point was only that the power curve of the graph was in agreement with the 100 ft-lb @ 6200 rpm number officially given by Kawasaki, and that although the torque curve is obviously placed too high on the graph, the overall shape of the torque curve is consistent with what you would expect if you assume that the VVT will be effective. Note, though, that there is a popular understanding of the advantage of having a flat torque curve, that isn't correct. It is nice for the acceleration to be very steady in 1st gear once you reach a certain road speed, and to remain steady for a short while. But, if are maximimizing the acceleration whilst running through the gears, the optimal shift points occur at road speeds where the engine speed will transition between equal-power points on opposite sides of the power peak. Looking at the dyno chart, or any dyno chart, it is easy to see that when you ride or drive that way, you keep the engine speed in the range where you are always on the down-sloping upper portion of the torque curve. You would not shift to 2nd gear until you have gone well past the flat region of the torque curve, and on subsequent up-shifts, the drop in engine speed will not be sufficient to return to the flat region of the torque curve. Hence, the supposed advantage of having a very flat torque curve around the torque peak is not really that much of an advantage. Rather, what is advantageous, is to have a torque curve that declines very gradually and very smoothly above the torque peak, because that is what leads to the power curve being comparatively flat and broad in the region around the power peak.

at which time Connie will purr out 159.41 HP
Assuming that the chart is legitimate ...

leaving yet a few ponies in the barn to be gingerly coaked and released after applying a few aftermarket remedies
I tend to be skeptical about the potential for after-market gizmos to have any appreciable benefit for performance, with the possible exception being when you have replaced the pipe and have thus caused the engine's breathing characteristics to differ from what they were when the ECU's stored tables were empirically defined.

The popular view is often that as a result of government-mandated requirements for emissions reductions, modern engines have untapped potential. I think that the opposite is true. A modern fuel-injection system with its many sensors and detailed fuel map will operate very close to the stoichiometrically correct mixture. It is generally true that there will be a slight power gain if the mixture ratio is slightly enriched, but the actual gain is marginal, and besides, the standard practice is to shift the mixture ratio to the empirically-determined optimal ratio for power, as soon as the throttle position sensor indicates that the operator wants more power. The question that perplexes me about the popular gizmo, is that unless it has some way to determine whether the ECU has shifted the mixture ratio to the optimal ratio for power, how could it possibly avoid over-enrichment of the fuel mixture at those times when the ECU sets the mixture ratio to the optimal ratio for power? It simply is not possible to avoid that detrimental effect by looking at the engine speed alone, because the engine speed is not adequate information to deduce whether the ECU has shifted the mixture ratio to the optimal ratio for power.

The actual effects of operating at an excessively rich mixture, aside from the reduction of power, will include causing the engine to run slightly cooler, since the unburnt fuel will have a net endothermic effect due to the absorption of energy at the change of phase from liquid to gas. Additionally, the fuel consumption will increase, and of course the emissions will increase, even if there is a catalytic convertor. Another potential beneficial effect of overriding the ECU and applying a slight enrichment, may be to achieve a small amount of smoothing of the transitions from off-throttle to slightly open throttle. The popular notion that running the mixture too lean will lead to "surging", is explained by the application of a fuel cut-off algorithm. It is possible to operate an engine at a mixture ratio that is far, far leaner than what is routinely necessary, with the amount of power produced being just enough to keep the engine running smoothly at idle. When the throttle is fully closed, the ECU will shift to this mode. If appropriate filtering/smoothing is applied to the transitions in and out of this mode, it should be difficult for the rider to notice the transitions. However, in some implementations, it is apparently the case that no filtering/smoothing is applied to the transitions from this mode back to the normal mode. Additionally, the unit-to-unit variation in the actual electrical resistance of the sensor (potentiometer) at the closed end of the range, is such that in order to insure that the fuel cut-off algorithm will trigger at all, the threshold has to be set at a position where the throttle is not quite fully closed. Combine that with the lack of smoothing, and the net effect is that you have a throttle position, not quite fully closed, where anytime that the rider tries to hold the throttle at that position, slight variations in the throttle position that are too slight to be deemed significant to the rider, can cause the ECU to switch in and out of the fuel cut-off mode.

But again, if appropriate smoothing is applied, the rider should only barely be able to notice the transitions, if at all, and if it happens that enriching the mixture ratio will reduce the abruptness of the transitions, that effect would be marginal at best. Some FJRs exhibited this problem to a slight degree, but it is likely that the principal cause was a bunch of faulty throttle position sensors, which were recalled by Yamaha and replaced.

Excluding the scenario where you have replaced the pipe, what you are left with is the strong likelihood that when your ECU has set the mixture at the optimal ratio for power, the gizmo will cause the ratio to be too rich. Unless the gizmo is intelligently coupled to the ECU in a way that allows the gizmo to know when the ECU has enriched the mixture to the optimal setting for power, the effect of the gizmo will be detrimental to power at the times when maximum power is requested by the rider. Even if the gizmo were to receive the signal from the O2 sensor, not even that would help, because the standard O2 sensor that is used in all but a very small percentage of vehicular applications, is only useful for maintaining the mixture at the stoichiometrically correct point, and is useless for attempting to maintain the mixture at the optimal point for power. When an ECU shifts the mixture ratio to the optimal ratio for power, it is ignoring the O2 sensor and operating in "open loop" mode, without feedback from the sensor, and using only the environmental sensors and the stored tables. The standard practice when installing this gizmo, seems to be to disconnect the O2 sensor from the ECU, since that will cause the ECU to operate full-time in open-loop mode. But the logic of this is flawed, because all that will do is prevent the ECU from going nuts trying to maintain the mixture at the stoichiometrically correct ratio. The stored maps that govern open-loop operation are still set up for stoichiometric operation, and an enrichment factor will still be applied based primarily on the throttle position.

If you replace the pipe, it is possible that the breathing characteristics of the engine will be altered so greatly from what they were when the stored tables were empirically defined, that the open-loop operation will be thrown off. It is also possible, but less likely, that the breathing characteristics will be altered enough to cause the ECU to detect an "out of range" error, i.e., during closed-loop operation, the adjustment that the ECU has to apply to the open-loop setting, in order for the O2 sensor to indicate that the mixture is stoichiometrically correct, is greater than the maximum adjustment allowed by the programming of the ECU. If that happens, you'll have to disconnect the O2 sensor and force the ECU to operate full-time in open-loop mode, whether or not you install the gizmo. When some of the FJR owners starting installing these gizmos and disconnecting their O2 sensors, I inquired as to whether any of them had conducted a controlled experiment, i.e., had compared the effect of forcing the engine to operate full time in open-loop mode, with the combined effect of that plus the gizmo. I made that inquiry on one of the most popular FJR forums, and yet not a single person who had installed the gizmo gave any indication that they had performed such an experiment, and several of them even indicated that they were confident that to do that would be a waste of time.

The bottom line is that the one scenario where the gizmo could potentially yield a positive benefit for power, is where it is used to correct for the effect of an after-market pipe altering the breathing characteristics of the engine. But even in that scenario, as I have repeatedly tried to point out, unless the gizmo receives a signal from the ECU that tells the gizmo whether the ECU has set the ratio to the stoichiometrically correct ratio or the slightly richer ratio that is optimal for power, there just doesn't seem to be any way that the net effect could be an improvement over what the ECU will do on its own if the pipe is left alone. When you consider that alongside the minimal gains that are possible when the pipe is replaced and when a top-notch professional team of engineers is put to the task of putting the fueling back in order, to my way of thinking, it just doesn't add up to an economically prudent strategy. If that potential 5% improvement is that important to you, then you have bought the wrong bike to start with. This is why I do not want to replace the pipe on any newer bike that I buy. The pipe is an integral part of a system, with part of that system being the tables that are stored in the ECU and that are used to manage the fueling in open-loop mode and for the base setting in closed-loop mode. These modern systems are phenomenally complex and precise right from the factory. When I sat down and started studying the factory service manual for the FJR, which manual has a ton of information on the theory and design of the engine management, I was stunned at the extent of the complexity and sophistication. I was accustomed to seeing this in automobiles, but not in a motorcycle. Gone are the days when your carburetor worked good enough as long as your engine didn't overheat and your plugs didn't foul. In those days, if you had the best engineer work long and hard with the help of a dyno and a good EGA, if you were able to get the fueling any closer, than is the stoichiometric point, to the optimal ratio for power, that would only be for one particular engine speed, and one particular throttle position, and one particular atmospheric density. Any modern engine, straight from the factory, is going to do a hundred times better, even if it operates at the stoichiometric point full time.
 

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Uhhh... :tard

Okay Mr. Engineer.... I'm an Iowa Farm-Boy. Does it go fast enough out of the crate? Probably. That's enough for me to know. :rofl
 

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Consider also that the C-14 is the only SPORT Touring Motorcycle that will be utilizing a pressurized air box. Ram air can add a nice boost at the top end.:evil
 

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Well of course. My point was only that the power curve of the graph was in agreement with the 100 ft-lb @ 6200 rpm number officially given by Kawasaki, and that although the torque curve is obviously placed too high on the graph, the overall shape of the torque curve is consistent with what you would expect if you assume that the VVT will be effective. Note, though, that there is a popular understanding of the advantage of having a flat torque curve, that isn't correct. It is nice for the acceleration to be very steady in 1st gear once you reach a certain road speed, and to remain steady for a short while. But, if are maximimizing the acceleration whilst running through the gears, the optimal shift points occur at road speeds where the engine speed will transition between equal-power points on opposite sides of the power peak. Looking at the dyno chart, or any dyno chart, it is easy to see that when you ride or drive that way, you keep the engine speed in the range where you are always on the down-sloping upper portion of the torque curve. You would not shift to 2nd gear until you have gone well past the flat region of the torque curve, and on subsequent up-shifts, the drop in engine speed will not be sufficient to return to the flat region of the torque curve. Hence, the supposed advantage of having a very flat torque curve around the torque peak is not really that much of an advantage. Rather, what is advantageous, is to have a torque curve that declines very gradually and very smoothly above the torque peak, because that is what leads to the power curve being comparatively flat and broad in the region around the power peak.



Assuming that the chart is legitimate ...



I tend to be skeptical about the potential for after-market gizmos to have any appreciable benefit for performance, with the possible exception being when you have replaced the pipe and have thus caused the engine's breathing characteristics to differ from what they were when the ECU's stored tables were empirically defined.

The popular view is often that as a result of government-mandated requirements for emissions reductions, modern engines have untapped potential. I think that the opposite is true. A modern fuel-injection system with its many sensors and detailed fuel map will operate very close to the stoichiometrically correct mixture. It is generally true that there will be a slight power gain if the mixture ratio is slightly enriched, but the actual gain is marginal, and besides, the standard practice is to shift the mixture ratio to the empirically-determined optimal ratio for power, as soon as the throttle position sensor indicates that the operator wants more power. The question that perplexes me about the popular gizmo, is that unless it has some way to determine whether the ECU has shifted the mixture ratio to the optimal ratio for power, how could it possibly avoid over-enrichment of the fuel mixture at those times when the ECU sets the mixture ratio to the optimal ratio for power? It simply is not possible to avoid that detrimental effect by looking at the engine speed alone, because the engine speed is not adequate information to deduce whether the ECU has shifted the mixture ratio to the optimal ratio for power.

The actual effects of operating at an excessively rich mixture, aside from the reduction of power, will include causing the engine to run slightly cooler, since the unburnt fuel will have a net endothermic effect due to the absorption of energy at the change of phase from liquid to gas. Additionally, the fuel consumption will increase, and of course the emissions will increase, even if there is a catalytic convertor. Another potential beneficial effect of overriding the ECU and applying a slight enrichment, may be to achieve a small amount of smoothing of the transitions from off-throttle to slightly open throttle. The popular notion that running the mixture too lean will lead to "surging", is explained by the application of a fuel cut-off algorithm. It is possible to operate an engine at a mixture ratio that is far, far leaner than what is routinely necessary, with the amount of power produced being just enough to keep the engine running smoothly at idle. When the throttle is fully closed, the ECU will shift to this mode. If appropriate filtering/smoothing is applied to the transitions in and out of this mode, it should be difficult for the rider to notice the transitions. However, in some implementations, it is apparently the case that no filtering/smoothing is applied to the transitions from this mode back to the normal mode. Additionally, the unit-to-unit variation in the actual electrical resistance of the sensor (potentiometer) at the closed end of the range, is such that in order to insure that the fuel cut-off algorithm will trigger at all, the threshold has to be set at a position where the throttle is not quite fully closed. Combine that with the lack of smoothing, and the net effect is that you have a throttle position, not quite fully closed, where anytime that the rider tries to hold the throttle at that position, slight variations in the throttle position that are too slight to be deemed significant to the rider, can cause the ECU to switch in and out of the fuel cut-off mode.

But again, if appropriate smoothing is applied, the rider should only barely be able to notice the transitions, if at all, and if it happens that enriching the mixture ratio will reduce the abruptness of the transitions, that effect would be marginal at best. Some FJRs exhibited this problem to a slight degree, but it is likely that the principal cause was a bunch of faulty throttle position sensors, which were recalled by Yamaha and replaced.

Excluding the scenario where you have replaced the pipe, what you are left with is the strong likelihood that when your ECU has set the mixture at the optimal ratio for power, the gizmo will cause the ratio to be too rich. Unless the gizmo is intelligently coupled to the ECU in a way that allows the gizmo to know when the ECU has enriched the mixture to the optimal setting for power, the effect of the gizmo will be detrimental to power at the times when maximum power is requested by the rider. Even if the gizmo were to receive the signal from the O2 sensor, not even that would help, because the standard O2 sensor that is used in all but a very small percentage of vehicular applications, is only useful for maintaining the mixture at the stoichiometrically correct point, and is useless for attempting to maintain the mixture at the optimal point for power. When an ECU shifts the mixture ratio to the optimal ratio for power, it is ignoring the O2 sensor and operating in "open loop" mode, without feedback from the sensor, and using only the environmental sensors and the stored tables. The standard practice when installing this gizmo, seems to be to disconnect the O2 sensor from the ECU, since that will cause the ECU to operate full-time in open-loop mode. But the logic of this is flawed, because all that will do is prevent the ECU from going nuts trying to maintain the mixture at the stoichiometrically correct ratio. The stored maps that govern open-loop operation are still set up for stoichiometric operation, and an enrichment factor will still be applied based primarily on the throttle position.

If you replace the pipe, it is possible that the breathing characteristics of the engine will be altered so greatly from what they were when the stored tables were empirically defined, that the open-loop operation will be thrown off. It is also possible, but less likely, that the breathing characteristics will be altered enough to cause the ECU to detect an "out of range" error, i.e., during closed-loop operation, the adjustment that the ECU has to apply to the open-loop setting, in order for the O2 sensor to indicate that the mixture is stoichiometrically correct, is greater than the maximum adjustment allowed by the programming of the ECU. If that happens, you'll have to disconnect the O2 sensor and force the ECU to operate full-time in open-loop mode, whether or not you install the gizmo. When some of the FJR owners starting installing these gizmos and disconnecting their O2 sensors, I inquired as to whether any of them had conducted a controlled experiment, i.e., had compared the effect of forcing the engine to operate full time in open-loop mode, with the combined effect of that plus the gizmo. I made that inquiry on one of the most popular FJR forums, and yet not a single person who had installed the gizmo gave any indication that they had performed such an experiment, and several of them even indicated that they were confident that to do that would be a waste of time.

The bottom line is that the one scenario where the gizmo could potentially yield a positive benefit for power, is where it is used to correct for the effect of an after-market pipe altering the breathing characteristics of the engine. But even in that scenario, as I have repeatedly tried to point out, unless the gizmo receives a signal from the ECU that tells the gizmo whether the ECU has set the ratio to the stoichiometrically correct ratio or the slightly richer ratio that is optimal for power, there just doesn't seem to be any way that the net effect could be an improvement over what the ECU will do on its own if the pipe is left alone. When you consider that alongside the minimal gains that are possible when the pipe is replaced and when a top-notch professional team of engineers is put to the task of putting the fueling back in order, to my way of thinking, it just doesn't add up to an economically prudent strategy. If that potential 5% improvement is that important to you, then you have bought the wrong bike to start with. This is why I do not want to replace the pipe on any newer bike that I buy. The pipe is an integral part of a system, with part of that system being the tables that are stored in the ECU and that are used to manage the fueling in open-loop mode and for the base setting in closed-loop mode. These modern systems are phenomenally complex and precise right from the factory. When I sat down and started studying the factory service manual for the FJR, which manual has a ton of information on the theory and design of the engine management, I was stunned at the extent of the complexity and sophistication. I was accustomed to seeing this in automobiles, but not in a motorcycle. Gone are the days when your carburetor worked good enough as long as your engine didn't overheat and your plugs didn't foul. In those days, if you had the best engineer work long and hard with the help of a dyno and a good EGA, if you were able to get the fueling any closer, than is the stoichiometric point, to the optimal ratio for power, that would only be for one particular engine speed, and one particular throttle position, and one particular atmospheric density. Any modern engine, straight from the factory, is going to do a hundred times better, even if it operates at the stoichiometric point full time.

Damn you're making my brain hurt! You could have just said that modern engines tuned with modern electronics are at their optimum efficiency and therfore would not benifit from said gizmo (power commander???)to any appreciable degree.:rofl :runaway
 

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I tend to be skeptical about the potential for after-market gizmos to have any appreciable benefit for performance, with the possible exception being when you have replaced the pipe and have thus caused the engine's breathing characteristics to differ from what they were when the ECU's stored tables were empirically defined.
I saw many times that factory settings are not optimum, even I have strong believe that factory setup is best for most of the drivers. I gave my trust to their labs and army of experienced engeneers, So is very hard to archieve better setup than factory, but it's rellatively very easy for tuners with enough experience, know-how and High-Tech parts and machines. In such a situations, I usually remind me on test-sheet of BMW R 1200 GS and tested 12 after-market exhausts, where's been showed exactly how much Nm, HP and other precise specs gives each of tested exemplares.

Of course, "ground stone" for that measurement and results was factory fitted exhaust. From that 12 exhausts, only 4 of them gave more than factory setup (all other was under!), and power (in factory serial model is 98 HP) varied from 93 to 104 HP, and torque was not even in these limits to find; I mean boost of torque was even rare than HP, and prices for such after-market solutions are much to high in comparison of benefit. Even one sound-name like Akrapovič failed in comparison to factory exhaust, only one (Bos) archieved bigger growth in power and torque, and both without breaking noise limitations. Yoshimura was even like BMW made, so where's the point?? In additional 500 euros for nothing!

I really don't know who - from normal, ordinary, everyday amateur drivers - needs, or has some real meaning, in additional 2 or 4 HP, or 5 Nm of torque?? I don't believe in such a stories, they sounds like looking for appologize why they throw away money, without any real benefit in praxis.
 
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