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Questions for Birdman

5212 Views 26 Replies 5 Participants Last post by  Birdman45
I sauntered over to the 600rr site after reading your side bar with Tim R regarding an argument you were having with Marc Salvisberg. After a brief search, I located this exchange and I am curious about some points you made in the debate.

Do you still think Factory Pro dyno's can "put in whatever load they want"? It's been made clear that in a steady state test, the dyno produces whatever load is required to hold the bike at the rpm test point. Less clear is the fact that with FP dynes the sweep rate is selectable. This may be what you're talking about, but the horsepower doesn't change.

Do you still think that 118 hp 600rr with only a slip-on is indicative of "normal" numbers for an FP dyno? Did you notice that was actually a Mustang dyno anyway?

Do you deny or contradict the story that Mark Dobeck added enough driveline inertia to the original DynoJet dyne software to make a VMax show 120 hp at the rear wheel, thereby skewing subsequent power measurement for decades to come? Do you really think this has no bearing or effect on the current lack of repeatability or standardization?

Do you doubt that Factory Pro dynes read within roughly 1/2 horsepower of each other?

Do you still maintain that steady state testing to best power at each rpm/TP is inferior to sweep tests, even though your dyno has no ability to do these tests, has no ability to measure power real time, and even though a Factory Pro dyno will do the sweep tests you like to use AND do them while showing real-time horsepower AND do them to a selectable acceleration rate to match the sweep rate to the power of the bike AND despite the fact that the person (Marc) whose equipment lets him measure power in real-time during the sweep says that the difference in power during a sweep after tuning to steady state is less than 0.3 horsepower?

Did you not notice that when Marc was agreeing that the only use for a dyno was to compare "before and after" - he was talking about DynoJet dynos and their complete inability to read anything close to one another?

Did you understand his point that, for literbikes, the acceleration rate allowed by a DJ dyno is too high? He was being nice and not slamming your dyno, but when reading between the lines when he's talking about 40 ft/sec/sec accel rate sweeps he was really saying sometimes the hp difference (b/w Factory and DJ dynos) in literbikes is not as great due to the fact that their combustion chambers never get up to real-life temperatures on an inertial dyno - the sweep happens too fast.

I'm stupefied that you seem to think you got the better of Salvisberg during that exchange. I'm confident you can prove me wrong here.
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hahahahaha. I'll say what Tim and I have talked about "off line" In the grand scheme of things, FP are ofno consequence. I ain't gonna bother to go through all that coz I did it with Marc on the posts you're talking about. I wil say that I know what I see with my own eyes. I have mapped bikes that are done on dynos here that work and show eactly the same things that the FP does and is supposed to be way more accurate , blah blah blah, and after I mapped them, they made more hp. I couldn't give a flying F$&K either way what you or Marc think about what I said, Marc chops and changes from one thing to another and will Never give a direct reply to anything, eg "no, applying ifferent loads to the sweep will not change h.p figures" and then in the next breath "well, obviously that run had incorrect sweep parameters loaded" Hahaa I thought it didn't matter?

When Marc puts up on his site, a comparison between his gear and anything except the first model DJ anything (dyno, PC etc) then I might listen a lil harder. But while you say "Our mapping tool is better than a PCII" Hahaha Yay for you.

Have fun
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Okay, let's try this:
Here's a cut and pasted question from Marc during your exhange. It has direct relevance to your assertion that fueling values derived from steady state testing do not translate into max horsepower during "real world" sweep tests:

Why does one dj "tune to an af ratio" in a loaded sweep test (w/o hp) and then test for djhp in an inertia sweep? The recorded af ratio in an "unloaded" inertia sweep surely is different, such as extrapolated logic would dictate based on your assumptions of steady state and sweep tests.>>
The fuelling at steady state and sweep is different on many bikes. Fine you tune at steady state for max bhp at a given load site then when rolling on abruptly some ecus decide to alter the fuelling (like an accelerator pump jet) and your ideal bhp figure is now fucked. You need to use a brain when mapping and understand the requirements for that particular machine. This is why i'm not a fan of tuning link because it takes feel away from the operator. In the same way i'd rather port a head by hand than have a cnc machine do it.

As for mapping at steady state being the only way to do it, watch an f1 engine dyno session and you will see massive acceleration rates because this is what happens to the engine on track!

I really can't see why all these arguments are relevant anyway. Everyone has their own opinions on what is right and what is wrong. Who is to say who is right or wrong?
I agree to a point with tuning link, but nobody worth a damn would ONLY use T/Link and just go off whatever it feeds you etc as the only way to map your bike. But anyway.................... like i said.................... irrelevent.

As for the litre bikes making more power, the point was that people jump on and say "FP dyno's read 14% lower then DJ dynos and are more accurate, Marc said so" well is that right or not? Regardless of why, is that true? NO so why tell people it is? LOL It's just one argument for one scenario and then change it for another, with everything that he speaks about. fact is the parameters do have a say in what h.p the FP dyno shows, and they do not read lower than DJ dyno's, if they did, you would never see a 1000cc bike on a dj dyno post lower stock numbers than a FP dyno, but fact is you do. So argue away but you can't argue with facts. LOL
Thanks for the explanation. One more question for you if you can stand it:

The "accelerator pump" feature of some ECUs causes extra fuel to be added during rapid accelerations (or is it rapid throttle movements?). Either way, extra duty time gets added to the injectors, screwing up your map.

My question is, how do stock bikes handle this? I've seen many postings on this problem, including DynoJet's absurd suggestion for how to tune around it on the GSXR 600/750. But the bike was developed to be able to cruise smoothly then suddenly whack the throttle open and have the bike respond without drama. They do a pretty good job with that, but once we add an exhaust and a PowerCommander, the same is no longer true.

I don't think I've worded this very clearly. I guess it comes down to 'why is this do-able with a stock ECU/exhaust, but so hard with a PC/new exhaust'?
I think the big problem at the moment facing the powercommander is the twin injector bikes. Some are worse than others for causing such issues. It depends on how much percent duty cycle of total each is using at the offending rpm. R1's and r6's have this nasty throttle snatch the moment you even look at the grip regardless of pc3 r not. Until they bring out a unit that controls both i can't see a perfect solution.

The powercommander and all other piggy-back units are all ultimately flawed and subject to skew because of the nature of how they operate - they adjust a map that has already been compensated by sensors attached to the ecu and do not take these into account. Ultimate solution is to remap stock ecu or fit a whole new ems.

Like i said earlier, all this talk is really irrelevant in most real world situations as the job all these units do is more than good enough in feel for the majority of users. How many decimal places do you need to work to? On machines where the response is still shit then there is usually a work around, such as frigging around with accelerator pump settings.

Just remember all those crap carburetted bikes we all rode in the past and thought were great!!!
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On the R6 racebikes I map for yamaha Oz, I spend alot of time rolling up to red line in say 3rd, and rolling back on at 2, 5% etc while it's still up in the rpm right up top where you don't usually get to due to the bike not revving that high on it's own accord, and adding fuel so that there is no lag between no throttle, the 2, 5 and 10% you pass through to get to the 20 and 40% you hit to drive out of the corner, that you mapped to be right, and so would normally get a "gap" of fueling. Smooth as apparently.
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I'll give that a go, cheers Trev.

Birdman45 said:
On the R6 racebikes I map for yamaha Oz, I spend alot of time rolling up to red line in say 3rd, and rolling back on at 2, 5% etc while it's still up in the rpm right up top where you don't usually get to due to the bike not revving that high on it's own accord, and adding fuel so that there is no lag between no throttle, the 2, 5 and 10% you pass through to get to the 20 and 40% you hit to drive out of the corner, that you mapped to be right, and so would normally get a "gap" of fueling. Smooth as apparently.
If you have an ignition module to play with , it can soften the pickup to take some timing out of the 0, 2, 5 % throttle position up there too.

Seems even smoother than adding fuel. :)
Kudos to Birdy, Tim and Dorkfish for an interesting discussion. It would be easy to let it deteriorate, but I'm having a great time reading all of this. Please keep it up, very informative. I'm learning. Whether or not the info contained here helps me in the real world (I don't tune bikes, just ride them) it is still fancinating stuff.

So being relatively new to all of this, my question to each of you is my understanding is that either FP dyno or DynoJet tuning will be beneficial whether or not it is done with a PC or FP's Teka unit?

Obviously, Tim and Birdy use the PC (and have a lot of experience with them), but have either of you ever used the Teka before? Just curious. It essentially does the same thing as a PC (depending upon who is claiming the benefits and take-aways). I've used the PC and had it customed mapped and it was great.

Thanks in advance to any and all responses.
The teka only adds fuel doesn't it? Pretty sure it does, and so is a waste of time and space. Please, feel free to tell me otherwise, wouldn't be the first time I've got it wrong, but most of the so called "better" and "easier" units to use only add fuel. Problem is, most of your map requires fuel to be removed, and so, how can that be what you want for your bike?
"Seems even smoother than adding fuel."

Thing I have found when doing it though is that when you get up to redline, back off and at 9-10K rpm, when you get back on, you turn the throttle and it's lean at 2 and at 5 and so on until you get to where you have actually mapped up to (ie: a TP that will rev the bike that hard) Adding the fuel there makes it a more linear transition from getting back on and then accelerating again etc.
The Teka SFI (Suzuki Fuel Injection) tool can add or subtract fuel. It plugs into the stock Denso ECU, allowing the tuner to add or subtract fuel in 5 different throttle position ranges. Additionally, idle can be adjusted for each cylinder individually. All changes, whether adding or subtracting fuel are permanently stored in the stock ECU. The Teka SFI is a real time device. There's no need to shut the bike down, make a change, fire the bike back up and return to the test point. When used in conjuction with a load-controlling dyno that can measure horsepower in real time, the tuner can hold the throttle at the desired position, let the dyno hold the rpm steady at the desired test point, and make an input (either adding or subtracting fuel by the way). If horsepower goes up, continue in that direction. If it keeps gaining power, keep going till it loses power, then fiddle around till you've maxed it out. The only pause in this whole procedure is to allow the engine coolant or case temperature to return to the desired range. You can actually hear the sound of the engine change as you make changes with the Teka tool. This sounds a bit labor intensive, but with a high-speed 4-gas analyser, an interesting thing happens: once you have found Best Power at one RPM and throttle position, the exhaust gasses become sorta like a snapshot of what Best Power looks like in that engine. So you know which way to go during the next test, and you also know about how far to go. Subsequent rpm/tp points take much less time to zero in on. An added bonus is that nothing is left on the bike - you disconnect it and put it away. On the minus side, the tool only works with stock Suzuki Denso ECUs, so don't be talking it up to some poor sap with a Kawasaki.

You're already familiar with PCs. Not a thing wrong with the concept. If you can't directly access the ECU to make changes, making them afterward is a fine idea. The problem is that too many people have been duped into believing you can bum a map from a buddy or download one off the internet and have your bike run right. On this forum right now, I bet you could find half a dozen reasonably-current requests for maps or threads with titles such as "Just Got it Mapped, Now it's Hard to Start" or something similar. Seems to me there's something wrong somewhere.
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Agreed and exactly as i stated earlier in this thread.
Whether or not you can get the desired resolution is another matter but you will never have a perfect unit even if you spend 10k on something like a motec!!
How much are the teka programming units and who sells them? What rpm resolution can you get?

Tim Radley said:
The powercommander and all other piggy-back units are all ultimately flawed and subject to skew because of the nature of how they operate - they adjust a map that has already been compensated by sensors attached to the ecu and do not take these into account. Ultimate solution is to remap stock ecu or fit a whole new ems.
well by the "5 different positions" I'd still say it is nowhere near as good. What your bike does at 20% throttle and 4000rpm and then at 20% throttle and 10000rpm can be very different. So you will be always robbing peter to pay paul. Add to that, again, once you find "max power" by holding your bike at a set rpm and TP, and getting that air'fuel ratio, once you put the bike into "real life" where it passes through an rpm under load, that air/fuel and so the max power goes straight out the window. LOL

I agree that PC's aren't used the way they are supposed to be quite often and any of us, Tim, myself or anyone else worth a dime that does mapping etc, will always post on forums (and get smashed for it)_ that you should have your bike custom mapped. IN saying that, there are people that have used downloaded maps etc that love them so I wouldn't say everyone that gets a PC and doesn't have it mapped on a dyno is unhappy etc. But again, for the $'s spent, the time and effort on the dyno and the parameters that you can work in, I can't see much that is better than a PC on the market for the $'s.
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Birdman continues to equate horsepower with residual oxygen. Folks with a dyno that can be programmed to replicate the acceleration rate of a real motorcycle while simultaneously measuring horsepower real-time in a sweep test have informed him that what he keeps saying about steady-state versus sweep testing (that steady state fueling values are invalid as the rpm changes in a sweep) is just wrong. The difference is 0.2-0.3 horsepower. Of course a DynoJet 250i dyno won't tell you that, so he insists it is so since the "A/F ratio" is all messed up it must be making less power. This says far more about the usefulness of measuring residual oxygen and trying to make that number "right" than it does anything else.

System A can closely-hold the motor at a steady rpm, make fueling changes, and measure the results in real-time horsepower. It can then be used to verify those results with a sweep test whose rate of acceleration can be selected to approximate the actual motorcycle being tested. During said sweep test, horsepower is being measured and displayed in real time. The guy who invented this dyno says that after many thousands of comparisons, they've found the actual horsepower at a given rpm varies roughly 0.2-0.3 horsepower between steady state and sweep results.

System B uses the inertia of a 900lb drum to back into a horsepower measurement. The drum is accelerated from a low rpm to high rpm and the time it takes to do that is turned into a horsepower calculation. Additionally, the system has an eddy-current retarder on it. This slows the rate of acceleration of the drum enough so that a probe in the exhaust can measure residual oxygen at a given rpm. This is extrapolated into an "air/fuel ratio" which is the primary goal of tuning on System B. An "air/fuel" ratio of (insert current number here) will produce the most power. Fueling changes are made to make the A/F ratio look right. Then horsepower is measured again, the way it has always been measured by System B - another low to high rpm sweep test.

Which system sounds like the more advanced system to you, Duder?
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Other points to ponder:
1. What's harder: accelerating a real bike on the road from 3000 to 13000 rpm in 1st gear, or in 6th gear?
2. What's harder: accelerating a 900 lb drum from 3000 to 13000 in 1st gear, or doing it in 6th gear?
3. No matter what gear you're in or how much horsepower you have, what's harder: accelerating from 60-80 mph, or accelerating from 120-140 mph?
4. Do bikes accelerate at the same rate throughout their rpm ranges, or does the rate tend to change approaching redline?
5 As an inertial drum gets spun toward redline in 6th (maybe 175mph) versus in 1st (maybe 100 mph), there's more drag. Is this amount of increased drag enough to simulate the increased wind resistance?
What make of dyno do you own or operate?
None, Tim. I'm in the "Someone Talk Me Out of This Stage". I keep trying to learn why DynoJet should have the honor of being the most-used dyno in the tuning business. The more I learn, the more convinced I become that technology and the requirements of fuel injection tuning has passed their system by. You, on the other hand, actually make a living doing this, so when you talk, I listen. I like arguing with Birdman because it's sorta easy when he keeps saying wrong stuff. By the way, I DO NOT doubt that either of you can make a bike scream like a banshee. I just think that it's your experience that allows you to tune around your dyno's limitations and that as we progress down the trail of time, there will come a day when there are no tuners who grew up tuning slide carbs and all they'll know is "tune to XX.X% AFR". No clue how to make the bike run right.

For the record, I'm shopping Factory Pro EC-997s, DynoJet 250is, trying to get smart on Land and Sea's dyno, as well as Superflo's. I like to take a position and see if someone can knock me off of it. You've been too nice to do it so far.
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