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[Trapperdog]

 

[Heatwave]

Once again, congrats to Lever on a very nice build. Enjoy...I know exactly how much fun you're having. And now others know exactly how to turn their tame 110" into the same kinda fun-riding beast!

[glens]

I get my bike tuned at another shop a year ago and the results are 111/115 SAE.


The bike runs well but I believe there's more "left on the table". So I take the bike to Joe's and while I"M STANDING THERE he does a baseline dyno run. He has no idea what the bike is capable of. The baseline comes back at 111/114, once again while I'm standing next to Joe on the bike with ear covers watching the screen. Is it that unreasonable to conclude that these 2 dyno runs, made 200 miles and a year apart by 2 different operators can reasonably be interpreted as the dyno's are showing consistent results. What the h*ll other interpretation can there be??

Look, you state the first set is SAE.  Fine.  But no information as to the level of "smoothing".  Then you say the subsequent baseline is nearly the same numbers, but don't specify what sort of, if any, correction is applied, nor what level of smoothing.  Since the numbers are made up out of thin air anyway (yes, they are), I guess it's possibly a testament to consistency between dynos and the mechanisms/algorithms at play.  But there's too little information provided to really come to that conclusion, right?

Then I get Joe's final tune and it comes back as 129/129 actual and 123/123 SAE. This is not a complicated story and the results speak for themselves even if other's feel a need to come up with some incredible fantasy to suggest otherwise.

The "actual" numbers aren't "actual" in any event, and without correction factors for air temperature and pressure (SAE) any numbers are especially meaningless.  You wouldn't want to perform a baseline in "actual", then work on the bike and later in the day perform a comparison run again in "actual".  At least not unless your dyno room is temperature and pressure controlled at least.

I wonder what sort of tune the original tuner could provide on that same bike now after this time has passed and the engine has broken in more completely.  I'm not raggin' on Joe (I don't have a clue who he is) or on his dyno.  I guess it could be said I'm raggin' on reported dyno numbers in general.  They really are meaningless and if you understood (better?) the how and the why of it then life would evidently be a little easier for you.  I say that based upon what I've seen here today.  It looks like you're a bit worked up.  I think it's a shame because it's unnecessary.

There are way too many numbers and charts being thrown around for me to follow this well.  Also a factor is that I really don't understand the mindset.  If a bike is tuned well and it operates well, that's the only proof that matters.

[Heatwave]

Look, you state the first set is SAE.  Fine.  But no information as to the level of "smoothing".  Then you say the subsequent baseline is nearly the same numbers, but don't specify what sort of, if any, correction is applied, nor what level of smoothing.  Since the numbers are made up out of thin air anyway (yes, they are), I guess it's possibly a testament to consistency between dynos and the mechanisms/algorithms at play.  But there's too little information provided to really come to that conclusion, right?

The "actual" numbers aren't "actual" in any event, and without correction factors for air temperature and pressure (SAE) any numbers are especially meaningless.  You wouldn't want to perform a baseline in "actual", then work on the bike and later in the day perform a comparison run again in "actual".  At least not unless your dyno room is temperature and pressure controlled at least.

I wonder what sort of tune the original tuner could provide on that same bike now after this time has passed and the engine has broken in more completely.  I'm not raggin' on Joe (I don't have a clue who he is) or on his dyno.  I guess it could be said I'm raggin' on reported dyno numbers in general.  They really are meaningless and if you understood (better?) the how and the why of it then life would evidently be a little easier for you.  I say that based upon what I've seen here today.  It looks like you're a bit worked up.  I think it's a shame because it's unnecessary.

There are way too many numbers and charts being thrown around for me to follow this well.  Also a factor is that I really don't understand the mindset.  If a bike is tuned well and it operates well, that's the only proof that matters.

What is it with some of you guys? It's one attack after another. I tried to share my data that aligns well with the OPs build and performance and some of you want to turn it all into some mission against Hillside and Joe's tuning. Give it a rest. I was trying to help the next guy out with some data that supports the performance that Lever has experienced with his latest build. I could care less if others accept it or not. I've tried to answer questions where I had additional information that might help others. If it doesn't align with your preconceived views, feel free to move on. To those that are interested, I hope the additional information is helpful.

I've posted the data that's available and it strongly aligns to Lever's performance, and some of you just can't accept the dyno graphs and performance experienced.

The level of smoothing is going to have very little to do with peak #s. Smoothing on the graph will hide or show overall tuning flaws. It also makes the chart easier to read but getting overly hung up on what smoothing factor was applied is absurd. I happen to prefer seeing the graph with smoothing set to "0", but that's just me.

"Actual" is a "real term" that is printed on the graph of a DJ dyno and smply means there's no correction. It's the "actual" dyno performance with the temp, barometric pressure and humidity at the time of the run. That makes it the "actual" graph.

Given your self-professed "limited understanding" of dyno graphs, why would the topic even matter to you? Just because you think your bike is running well, doesn't necessarily mean its running as well as it can. In the absence of dyno runs where variables are considered, you'll never know if you bike is running at 90% of its capability or 50% of its capability. I suppose for some, not knowing what you're missing is best. For others, trying to maximize the performance of their bike is both a hobby and a mission. If you're riding a mostly stock bike, I doubt you can understand that perspective.

[Lever]

yea my bike runs very well thanks  ....still kinda baby it with the new belt ...for those that don't know i broke my belt ...after talking to my Indy , i think it was a combo of things, the dyno runs that had been done on the bike( not stroker's place  ) but a nother place near my hd dealership .. and maybe a def. belt and my fault as well for not keeping the belt properly  adjusted at all times

now when my bike was tuned  it was a brand new motor  less then 20 miles  on her ..it was broken in on Stroker's dyno ,tuned etc what i may do later this summer  is have the tune rechecked and dyno'd again when i have a couple of thousand miles on her  and see if there is any changes ?

i do have the 30th front gear and yes pulls where done in 6th gear  not sure if that plays in any part of the dyno sheet or not  

[Heatwave]

yea my bike runs very well thanks  ....still kinda baby it with the new belt ...for those that don't know i broke my belt ...after talking to my Indy , i think it was a combo of things, the dyno runs that had been done on the bike( not stroker's place  ) but a nother place near my hd dealership .. and maybe a def. belt and my fault as well for not keeping the belt properly  adjusted at all times

now when my bike was tuned  it was a brand new motor  less then 20 miles  on her ..it was broken in on Stroker's dyno ,tuned etc what i may do later this summer  is have the tune rechecked and dyno'd again when i have a couple of thousand miles on her  and see if there is any changes ?

i do have the 30th front gear and yes pulls where done in 6th gear  not sure if that plays in any part of the dyno sheet or not   

Just curious. Did you replace with a stock HD belt or are there aftermarket upgrades for the belt? Did the belt break while riding on the road or on the dyno? Was the belt replacement covered under warranty?

[glens]

What is it with some of you guys? It's one attack after another.

Not any attacks on my part.

Smoothing on the graph will hide or show overall tuning flaws.

The graph is WOT, which is a very small part of overall tuning, and truth be told probably the least-used condition the engine ever sees.  I think you're thinking something other than what you're saying?

"Actual" is a "real term" ... the "actual" graph.

I never said otherwise.  What I said was the numbers are not actual.  They're made up.  A best-guess approximation.

Given your self-professed "limited understanding" of dyno graphs, why would the topic even matter to you?

Now you're just arguing for the sake of doing it?  I doubt I professed to limited understanding.  Perhaps you're thinking of someone else?

I'll bow out now and leave the last word to you if you want it.  There were some question marks in my reply but I didn't really mean them to be questions that I want or need an answer to at this time.  You're obviously in a defensive mode today.  If you review my posts at a later date perhaps you'll see them more along the lines I'd meant them.  That would be nice...

[Lever]

it was  after market belt ..Falcon   ...broke it on my way to work ... i felt froggy and really twisted the throttle  ..no warranty on belt i refused to let  the dealership work on my bike cause i don't want a bunch of people  riding my bike
I'm sure it happens ...  you bring your hot rod in to the shop and leave it there for work to be done ...  u know there are gonna to test ride and the shop will come alive ...saying wow you need to test ride this bike its fast its gotta be 1 of the fastest bike I've riddin... other guy says no way ..let me test ride it .... you get the picture  now   ...only my Indy and stroker have touched my completed  bike and i hope to keep it that way for a long time

[Heatwave]

Not any attacks on my part.

The graph is WOT, which is a very small part of overall tuning, and truth be told probably the least-used condition the engine ever sees.  I think you're thinking something other than what you're saying?

I never said otherwise.  What I said was the numbers are not actual.  They're made up.  A best-guess approximation.

Now you're just arguing for the sake of doing it?  I doubt I professed to limited understanding.  Perhaps you're thinking of someone else?

I'll bow out now and leave the last word to you if you want it.  There were some question marks in my reply but I didn't really mean them to be questions that I want or need an answer to at this time.  You're obviously in a defensive mode today.  If you review my posts at a later date perhaps you'll see them more along the lines I'd meant them.  That would be nice...

I've been riding motorcycles for 40 years and involved with dyno tuning efi bikes since some of the first HD efi's came on the market. I've done a fair amount of my own tuning with SEST and SEPST with Smarttune and PowerVision's log tuner. I know the difference between WOT dyno graphs and how little they impact every day riding. That's why if I do pay for a dyno tune I expect a cruise graph that show's the afr for both cyl in additional to wot. This is not to be defensive but simply responding to questions you've asked.

The #s on a dyno are not "made up". They represent algorithyms that attempt to reflect the physics involved with power generation and then applying it to the ground. I also have had my efi performance boat engine tuned (640hp) and the physics are the same. Essentially the question is whether the timing and fuel mixture can be optimized to maximize the performance of an engine's physical capacity. The fat and happy folks riding their bikes and satisfied with their performance without knowing if it's maximized....well ignorance may be bliss for them. For guy's like me that want to improve the performance and are willing to spend the money on engine improvements, there's is no alternative (at least today) to a dyno for optimizing fuel, air and timing to get the most power from a particular engine build. Most guy's won't and don't get it. You appear to be in that group and there's nothing wrong with that.

[glens]

Maybe it's not true, I don't know, I wasn't there.

"One of the biggest headaches of Dynojet's go-it-alone chassis-dyno project was figuring out how to assign meaningful power numbers in the face of unknown inertia from the moving parts of the hundreds or thousands of engine, drivetrain, and tire combinations.  Wrestling to fully understand inertia and powertrain losses, Dobeck and his team quickly realized that the standard physics formula of weight, time, and distance for converting acceleration into horsepower simply didn't work-the derived number was always lower than accepted numbers.  They poured on resources and burned up time and money investigating it, but no matter what they did, the math never added up.

Dynojet's final number-fudge was arbitrarily based on a number from the most powerful road-going motorcycle of the time, the '85 1,200cc Yamaha VMax.  The VMax had 145 advertised factory horsepower, which was far above the raw 90hp number spit out by the formula.  Meanwhile, existing aftermarket torque-cell engine dynamometers delivered numbers that clustered around 120.  Always a pragmatist, Dobeck finally ordered his Chief Engineer to doctor the math so that the Dynojet 100 measured 120 hp for a stock VMax.  And that was that: For once and forever, the power of everything else in the world would be relative to the '85 Yamaha VMax and a fudged imaginary number.  Dobeck's engineering staff was dismayed by the decision, but the Dynojet 100 exclusively measured surplus power available to accelerate the vehicle's mass-no more, no less-and that was true even if the modification was a low-inertia flywheel or lightweight wheels.  As long as the inertial dyno's numbers were repeatable, the critical question (did a particular modification make the engine accelerate faster or slower?) would be answered correctly."

from http://www.hotrod.com/thehistoryof/113_0603_dynojet_chassis_dyno/viewall.html

So what's changed?

If you used a DC or variable-frequency AC motor and could directly measure the power, I would pay attention to the numbers.  At any rate, nothing you said in apparently attempting to show me in error was successful because you didn't address what I'd said.  You set up straw men then knocked them down.

I doubt you're any more anal about wanting things right than I am, but you know what?  I know for a fact my bike ain't set up to deliver the most power it can at WOT.  I don't care.  I have it set up instead to be spot-on in all the places I actually use it.

I don't recall seeing any part-throttle graphs posted, nor anybody else mentioning them, so I wonder why it is you brought them up...

[Heatwave]

I think you've made MY point.

First, for those that don't care to optimize their engine for maximum performance, then upgrades don't matter and neither does dyno-tuning. Guys riding stock bikes or nearly stock bikes aren't going to care about dynos or maximizing engine performance. And clearly you fall into this camp as do the vast majority of bikers and bikes on the road. Once again nothing wrong with that.

Maxmized engine performance is not only about WOT. If a tuner is only optimizing a bike at WOT then he's ripping you off. I always get a cruise dyno graph at 3000 rpms and have posted them before. Go look them up if you're interested. It will tell you if you're afr is set to balance both performance and fuel economy and generally should be leaner in both cylinders than the afr at WOT.

Secondly, in the quote above there's only one sentence that matters "As long as the inertial dyno's numbers were repeatable, the critical question (did a particular modification make the engine accelerate faster or slower?) would be answered correctly."

And that is the point of DJ's dyno products. It uses algorithyms and physics and formulas to calculate against a standard. The standard simply doesn't matter. It is not trying to compare the "actual" hp to any other device other than one that can rotate it's drum. So its measurement of hp and tq is NOT comparable to a rocket engine or a rototiller but only to other motorcycles or devices that can properly rotate it's dyno drum. Get it? So a dyno allows the user to make adjustments to efi engine parameters like AFR, fuel mixture and spark advance. And then compare to previous settings to see if the performance against the standard is the same, higher or lower. It also can then compare results from 1 dyno to another assuming they are calibrated consistently. And by using SAE, the theory is that the "math" will standardize key variables in a dyno run like humidity, barometric temp and ambient temp and therefore make those SAE results comparable between different runs on different days and even between 2 calibrated dynos.

You can certainly challenge whether a particular dyno is set to DJ's calibration standards and you can even challenge whether the formulas behind SAE can reasonably standardize measurement from one dyno run to another regardless of external variables, but suggesting that dyno results are meaningless is clearly a statement from someone that doesn't understand the purpose of building and then tuning a bike for maximizing performance. (BTW aren't you the guy that doesn't even own a bike? My apologies if you own a bike but if you don't, then I "really" understand why you are confused!)

In the end Lever's bike appears to be maximizing the performance of the $ he spent to build his engine. And that conclusion can be reached by:
- the measurements achieved on the dyno while tuning his bike
- the comparison of his measurements to all other bikes that have been run on a calibrated dyno
- the measurements as compared to bike's with a similar build such as mine so long as the dyno was calibrated and we're comparing SAE metrics
- and finally and most importantly the smile on Lever's face when he accelerates from a light and kicks a** when running against 99% of all other Harleys on the road

[Heatwave]

Maybe it's not true, I don't know, I wasn't there.

"One of the biggest headaches of Dynojet's go-it-alone chassis-dyno project was figuring out how to assign meaningful power numbers in the face of unknown inertia from the moving parts of the hundreds or thousands of engine, drivetrain, and tire combinations.  Wrestling to fully understand inertia and powertrain losses, Dobeck and his team quickly realized that the standard physics formula of weight, time, and distance for converting acceleration into horsepower simply didn't work-the derived number was always lower than accepted numbers.  They poured on resources and burned up time and money investigating it, but no matter what they did, the math never added up.

Dynojet's final number-fudge was arbitrarily based on a number from the most powerful road-going motorcycle of the time, the '85 1,200cc Yamaha VMax.  The VMax had 145 advertised factory horsepower, which was far above the raw 90hp number spit out by the formula.  Meanwhile, existing aftermarket torque-cell engine dynamometers delivered numbers that clustered around 120.  Always a pragmatist, Dobeck finally ordered his Chief Engineer to doctor the math so that the Dynojet 100 measured 120 hp for a stock VMax.  And that was that: For once and forever, the power of everything else in the world would be relative to the '85 Yamaha VMax and a fudged imaginary number.  Dobeck's engineering staff was dismayed by the decision, but the Dynojet 100 exclusively measured surplus power available to accelerate the vehicle's mass-no more, no less-and that was true even if the modification was a low-inertia flywheel or lightweight wheels.  As long as the inertial dyno's numbers were repeatable, the critical question (did a particular modification make the engine accelerate faster or slower?) would be answered correctly."

from http://www.hotrod.com/thehistoryof/113_0603_dynojet_chassis_dyno/viewall.html

So what's changed?

If you used a DC or variable-frequency AC motor and could directly measure the power, I would pay attention to the numbers.  At any rate, nothing you said in apparently attempting to show me in error was successful because you didn't address what I'd said.  You set up straw men then knocked them down.

I doubt you're any more anal about wanting things right than I am, but you know what?  I know for a fact my bike ain't set up to deliver the most power it can at WOT.  I don't care.  I have it set up instead to be spot-on in all the places I actually use it.

I don't recall seeing any part-throttle graphs posted, nor anybody else mentioning them, so I wonder why it is you brought them up...

And exactly how did you conclude that "I have it set up instead to be spot-on in all the places I actually use it."?

[PASN YU]

Why don't all of you bench racers create a thread of your own to do your arguing?? That way you don't have to hijack everyone else's when they post a dyno sheet. It could be called, "The Bench Racers Dyno Arguments".   

[glens]

I'm certainly no bench racer, though I guess I'm guilty of arguing with one...

I think you've made MY point.

A bit less than you've made mine!

Maxmized engine performance is not only about WOT. If a tuner is only optimizing a bike at WOT then he's ripping you off. I always get a cruise dyno graph at 3000 rpms and have posted them before. Go look them up if you're interested. It will tell you if you're afr is set to balance both performance and fuel economy and generally should be leaner in both cylinders than the afr at WOT.

Thanks, but no thanks.  Not interested.  Regarding the first sentence, however, we're in complete agreement.  Or didn't you read what I wrote yesterday?

Secondly, in the quote above there's only one sentence that matters "As long as the inertial dyno's numbers were repeatable, the critical question (did a particular modification make the engine accelerate faster or slower?) would be answered correctly."

And that is the point of DJ's dyno products. ... It is not trying to compare the "actual" hp to any other device other than one that can rotate [n.b. "accelerate"] it's drum. So its measurement of hp and tq is NOT comparable to a rocket engine or a rototiller but only to other motorcycles or devices that can properly rotate it's dyno drum. Get it?

It's not measuring torque and horsepower, it's inferring them.  Actually, inferring the torque and deriving the hp from that, well, maybe the other way around, I forget.  But other than that, yes, I get it.  I'd thought you'd be able to discern that from what I'd said yesterday.

So a dyno allows the user to make adjustments to efi engine parameters like AFR, fuel mixture and spark advance. And then compare to previous settings to see if the performance against the standard is the same, higher or lower.  It also can then compare results from 1 dyno to another assuming they are calibrated [n.b. and operated] consistently. And by using SAE, the theory is that the "math" will standardize key variables in a dyno run like humidity, barometric temp and ambient temp and therefore make those SAE results comparable between different runs on different days and even between 2 calibrated dynos.

Basically quoting me yesterday to me today?  Fleshed out a little, obviously, but other than that it's what I plainly said.

You can certainly challenge whether a particular dyno is set to DJ's calibration standards and you can even challenge whether the formulas behind SAE can reasonably standardize measurement from one dyno run to another regardless of external variables, but suggesting that dyno results are meaningless is clearly a statement from someone that doesn't understand the purpose of building and then tuning a bike for maximizing performance. (BTW aren't you the guy that doesn't even own a bike? My apologies if you own a bike but if you don't, then I "really" understand why you are confused!)

I underlined your misunderstanding of what I'd said.  I didn't say the results are meaningless.  Quite the opposite.  What I'd said was the numbers aren't accurate.  They're relative on any given dyno (when everything's done correctly and consistently) but they're not real.  It's like the "AFR" trace values.  Unless the bike is being run on some sort of laboratory test-grade fuel, you're not likely to find gasoline that burns at an AFR of 14:6:1, though that's the figure hard-coded into the AFR probes to indicate the fuel has been burned at stoichiometric mixture.  You can set up to run stoich with pure ethanol at 9:1 and the probe will indicate this condition as 14.6:1.  Sure, you can (usually) rely on the numbers being relative when you make adjustments to the engine, but to say you've set it up to run, say, 13.8:1 AFR is not correct.  If you'd said instead "0.9452 lambda" you'd be saying something worth saying.

Aren't I the guy who doesn't even own a bike?  See?  You're thinking I'm someone else, as I suggested yesterday.

In the end Lever's bike appears to be maximizing the performance of the $ he spent to build his engine. And that conclusion can be reached by:
- the measurements achieved on the dyno while tuning his bike
- the comparison of his measurements to all other bikes that have been run on a calibrated dyno
- the measurements as compared to bike's with a similar build such as mine so long as the dyno was calibrated and we're comparing SAE metrics
- and finally and most importantly the smile on Lever's face when he accelerates from a light and kicks a** when running against 99% of all other Harleys on the road

I'll grant you items 1, and possibly 4, with caveats.  But for items 2 and 3, I cannot agree.  They're too vague.  You left out way too many variables such as what gear the bike was in, tire pressure, was the operator sitting on or standing next to the bike, etc.  If the same operator runs two bikes in exactly the same manner on the same machine, then you can use the dyno to accurately compare them.  But the true value in a dyno, as we've both said now, is to compare changes to the same bike.

And exactly how did you conclude that "I have it set up instead to be spot-on in all the places I actually use it."?

Do you understand how closed-loop EFI works and how to adjust the ECM so that it's making little to no change to its calculations as a result of the feedback it's gathering?  If so, then you should be able to understand how I did it.

Thank you for your time and consideration.  I apologize to everyone else for the diversion.

Congrats Lever!

[PASN YU]

If you're no bench racer, take it to the track and prove your arguments there. If any of you are arguing about a dyno sheet and it's characteristics, you are a bench racer. Quit hijacking other poeple's threads.