| Author | Message | ||
     Teeps |
Does anyone use the Dobeck TFI jet kit on their Ulysses? Opionions/comments on good or bad aspects welcome. (Not looking for comparison to Direct Link,that's a whole 'nuther subject matter.) | ||
| Teeps |
Guess no one has one of these things? | ||
| Stevem123 |
Never heard of it. I do have a DFO on my Road Glide with the magnetti Marelli FI and it works well. A lot of the guys running the older tube-frame early DDFI units were running the power commander with varying results. Some good some bad. The DDFI II is pretty well sorted out and is tuneable with the right software. There is a thread on here somewhere where they were tuning a ULY with the stock ECM and a stage 1 consisting of a free-flowing muffler and a free-flowing K&N air filter getting consistant 100 RWHP pulls on the dyno.  I wouldn't spend the money on something that may not give results you want. BC Steve | ||
| Trojan |
There are plenty of people running the Techlusion (Dobeck) TFi on XB models including the Ulysses. Some people love 'em, others don't. I think a lot depends on what other mods you have and how you set it up. We ALWAYS recommend setting up on a dyno for any fuel injection adjustment devices. | ||
| Teeps |
Trojan Posted on Friday, June 16, 2006 There are plenty of people running the Techlusion (Dobeck) TFi on XB models including the Ulysses. Some people love 'em, others don't. I think a lot depends on what other mods you have and how you set it up. We ALWAYS recommend setting up on a dyno for any fuel injection adjustment devices. Thanks Trojan, But, real dyno tuning is what I'm trying to avoid. For what I need to do (eliminate a lean(?) surge in the 1000 to 2500 rpm range), the seat of the pants dyno will suffice. (lots of in town riding done here) Currently the bike is stock, and will likely stay that way. | ||
| Teeps |
I can't believe no one has any anecdotes for me with regard to the Dobek/Teclusion TFI system.??????? I am not in a position to buy one of these Jet-Kits and have it not work. Or worse make things worse. So anyone with any experience, good or bad, give me a sign... (Message edited by teeps on June 19, 2006) | ||
| Jerseyguy |
Teeps, Drummer Racing Products has a great deal of experience with these on the XB12 & 9 models. What mods do have you made on your ULY? | ||
| Mb182 |
Teeps I tried a search on TFI for the last year and found 343 postings... TFI will only add fuel.. I have used several on other bikes with mixed results depending upon mods made. It is less effective than a race ECM or Direct Link.. but it costs less. I'm sure if you call their tech folks and talk about your application they can be of some help. They are usually very helpfull. MB (Message edited by MB182 on June 19, 2006) | ||
| Teeps |
Thanks for the replies. My bike is stock, all I'm looking to do is eliminate or reduce the surge in the lower rpm range (1k to 2.5k.) | ||
| Jerseyguy |
Teeps - The TFI will not help this but a Drummer slip on will.  | ||
| Teeps |
So,Jerseyguy, are selling one?  | ||
| Jerseyguy |
LOL, Go to WWW.KDFAB.COM. Kevin will hook you up with a Drummer. | ||
| John88030 |
Teeps, I have the same problem as you. We are not alone either. I think the best solution would be a remapped ECM from AL, however no such map exists. I am thinking of the TFI also. I want to keep the bike quiet and it would seem the stock muffler is the best for this. I believe an aftermarket muffler by itself would only make a lean running condition worse. John | ||
| Teeps |
Jerseyguy Posted on Monday, June 19, 2006 - LOL, Go to WWW.KDFAB.COM. Kevin will hook you up with a Drummer. No thanks; I like the Uly in stealth mode. | ||
| Teeps |
Mb182 Posted on Monday, June 19, 2006 Teeps TFI will only add fuel.. I have used several on other bikes with mixed results depending upon mods made. I'm looking to keep the bike stock, just make it run better. I'm sure if you call their tech folks and talk about your application they can be of some help. They are usually very helpfull. MB I'd be game to buy one, if it came with a satisfaction warranty. The 2 year defect warranty, while sounds good is meaningless, if I'm not happy with the results. | ||
| Frankf |
Adding a Drummer makes the lean surge worse, not better. They run lean stock, so adding a low flow exhaust makes the problem worse. Solutions are to either install a race ECM or have the stock ECM remaped. Vallejo Harley Davidson, Buell is doing remaps. Cost is $350 | ||
| John88030 |
Frankf, Vallejo HD "can" do the remaps. They do Al's work and it seems in an excellent fashion, however they have not done a stock map. It costs far more than $350.00. $250 for the "key", $100.00 for the map. I have been told it takes for more than $100.00 in dyno time to develop a map. If they could split the costs over several bikes at $100.00 each then ok. If only 1 or 2 persons are interested they couldn't recover their costs. If I am wrong maybe someone from Vallejo or AL could chime in and correct me. John (Message edited by john88030 on June 19, 2006) | ||
| Teeps |
So far no one has answered my question, other than in vague and ambiguous terms... I am disappointed; however, I guess no news could be conscrewed[sic] as a positive for the TFI Jet-Kit, no? | ||
| Frankf |
John, Terry at Vallejo quoted me $350 to do the map on my Uly. My understanding is they do not have a pre made map, but were going to work one up and recoup the cost over time. He had told me that I had to leave the bike there as it would take him a couple of days to get it worked out. | ||
| John88030 |
Frankf, if a map does become available for the stock ULY I'd be in. I even have a spare ECM on the way so there would be no downtime for my ride. I just want to get rid of these problems at the low end. My last three Harley's were FI bikes (big twin 98/2000/2002 and all worked perfect to me and they all ran open loop only, no O2 sensor at all. It's a shame with obviously poor running that neither Buell nor my Dealer will address the problem John | ||
| Teeps |
John88030 Posted on Tuesday, June 20, 2006 I just want to get rid of these problems at the low end. My last three Harley's were FI bikes (big twin 98/2000/2002 and all worked perfect to me and they all ran open loop only, no O2 sensor at all. It's a shame with obviously poor running that neither Buell nor my Dealer will address the problem John In the automotive world (in which I work) we have a terms for things like this called: "product characteristic" and "industry standard." (I am not making excuses here for Buell, or any other maker. I am only stating the facts, I deal with daily.) What that means is: the "problem" or "characteristic" is real, however the vehicle IS operating within the factory design spec. Do we like this "characteristic"? Probably not; can it be fixed? Maybe. In the case of the Ulysses surging, it will not be something that a dealer can fix (legally) without a factory design change and a procedure (TSB) that has been certified by the Government. I believe the surging problem with the Ulysses falls into this area. It is something that, yes, "they all do", but no, they are NOT broken. I don't like it, either. Our options, as owners, are: live with the characteristic, bitch about it (wait for Buell-H/D to come up with a fix) while living with it, or fix it ourselves. Which it appears Vallejo H/D is willing to do, for a price}. | ||
| Al_lighton |
While I'm not completely sure how to correct the surging issue that some have, I am very convinced that re-mapping alone is NOT the answer. It's taken me a while to understand the nature of the surging issue that folks are referring to. But I think I finally understand what the surging they describe feels like. And I've been doing a bunch of testing with a beta version of VDSTS and a scanalyzer on my S3 to understand it a bit. My S3 seems to exhibit the "problem" more than my Uly does, but after feeling it on my S3, I can notice it a little on my Uly. Frankly, it really doesn't bother me, I've always thought it was just the nature of the beast. But if the problem was worse than it is on my S3, I could certainly see how it could be viewed as unacceptably objectionable. I'm pretty sure is an artifact of the closed loop operation algorithms. As stated by many, it is something that happens during steady state operation between 2500 and 3500 RPM. This is clearly closed loop operational domain. The map isn't even in the equation during this operational domain, so there is no reason to believe that changing the map will affect the behavior. I'm also fairly convinced that the surging IS the result of several successive lean mis-fire or weak fire combustion events. My understanding of how the Buell ECM works is as follows. Note that this understanding is based on little pieces of info gleaned from all over, and some is from empirical observations. I do not have any privileged info on the specifics of how the Buell ECM works at the detailed algorithmic level. I don't certify it as 100% accurate, but I'd bet it's not too far off. The normal default operation is in open loop, from the map, with all kinds of factors (i.e., inlet temp, engine temp, AFV, Fuel pressure and injector size constants, etc) operating on the fueling seed map values. When the ECM has the right combination of signal inputs, it commands the fueling control into closed loop. Certain RPM and vehicle speed, temperature, throttle position (TP) and TP rate of change inputs are all prerequisites for entering closed loop operation. 2500-3500RPM, normal operating temperature >280F, TP angles less than 30 degrees, and low TP angle rate of change are reasonable values for closed loop operation, but I don't know the exact definitions from Buell. The ECM knows what injector duration it is commanding upon entering closed loop. It then responds to the O2 sensor voltage to command the injector duration longer if it sees the mixture going leaner, and shorter if it sees the mixture going richer. Gentle changes in the TP or RPM causes the ECM to make those mixture changes. If there were no RPM or TP changes, you would think it would continue to command the same injector duration. But it doesn't work that way. This is the voltage output response curve of the narrowband sensor that the bike is running on.  It's curve shape isn't an accident. It was engineered that way so that millions of cars could operate near or at the theoretically perfect stoichiometric A/F ratio of 14.7:1 for gasoline. If linear wideband sensors (more $$$) were utilized, they would all have to be kept within reasonably tight calibration levels to ensure the engine was fueling properly. But by using one with this very non-linear behavior, the control problem is much easier: keep the voltage in the middle of the vertical section of the curve, and you'll be at 14.7:1. However, ECMs that operate on these narrowband sensors work don't work by holding the fueling so that the output voltage is steady at 0.45V. Instead, they work by modifying the control input (injector duration) to oscillate the fueling back and forth across this 0.45V. If you hook up a scanalyzer onto a tube frame Buell (won't work on an XB), you can watch the O2 voltage directly, and you can see when the ECM enters closed loop. I've driven my S3 with the scanalyzer taped to the gas tank, watching the O2 sensor output. It hardly hovers on either side of .45V. Rather, it bounces back and forth routinely between .15-.20 Volts and .75-.80 volts. The oscillation period is 1-2 seconds. Note that these voltages are clearly beyond the knee of the curve on both the upper and lower sides, and into the correspondingly very-rich and very-lean zones. Yet, on average, it runs at 14.7:1 and would therefore likely pass emissions testing. It is my belief that the lean missing is due to the shorter injector durations being commanded when the closed loop injector duration is commanded on the shorter side of things. At 3600 RPM, there are 30 combustion events in one second. The observed O2 voltage oscillation by viewing the scanalyzer voltage in in the neighborhood of 1-2 seconds. The part I don't know is if the actual controlled oscillation is actually much faster than that, and I'm only seeing the sample rate rather than the actual voltage oscillation rate. But I think that the voltage oscillation is in the 1-2 second rate, because otherwise sequential samples would be randomly high or low, but they appear to be alternating high and low. If the ECM had a tighter loop control on this, where instead of jumping between .2 and .7 Volts, it jumped between .3 and .6 volts, I don't believe that one would experience the surging. My theory on why some peoples bikes are worse than others is that they are oscillating further on the lean side than bikes that aren't surging. If that theory is true, what would make the difference between bikes? Certainly the O2 sensor could. I wonder if there are substantial differences between the voltage output (or voltage slew rate) of sensors that could cause this. The electrical connections between the O2 sensor and the ECM may also be an issue. A .05V voltage drop across a non-gold plated contact would be significant for a 0-1 volt signal like the O2 sensors have. And the return path isn't through an electrical connector at all, it is through the O2 sensor body and the header, and then from the header to the frame ground. So perhaps that is another variable that is affecting the way different bikes are running in closed loop. Can anyone that has had the surging confirm that the issue existed across multiple O2 sensors and pipe swaps? But in answer to the original question in this thread, a TFI might help with the problem, but it may just be addressing the symptom rather than the cause. And it might even make things worse. In-between boxes like power commanders and TFI's modify (increase only for TFI) the injector duration sent from the ECM to the injectors. If it does this during closed loop, the ECM will notice the mixture going richer and lower the injector durations accordingly. But, since the AFV setting algorithm is also operating in closed loop, the additional fuel cut the ECM has to do to bring the O2 voltage back to where is wants it to be will likely cause the AFV to skew lower. So when the bike runs in open loop, the AFV will lean the bike out more. This is but one reason why I am not partial to in-between boxes on Buells. But the TFI has one pot that is specifically for controlling the O2 sensor input to the ECM. It sits between the narrowband O2 sensor and the ECM, and the 4th pot has some type of effect on that 0-1V signal feeding the ECM. If it essentially lowers that output by a little, the ECM would then compensate by pushing the fueling up a little in order to get the voltage between the values it is trying to hit. This would make the closed loop domain run a little richer overall. But I still have concerns that the AFV setting algorithm would then cause the AFV to get set on the low side. It is possible that with a combination of a TFI modifying the O2 sensor input, along with a directlink remapping that is compensating the AFV setting algorithm, that the best of both worlds could be achieved. But that is getting into a lot of expense. It sure seems to me that if there are some bikes that are doing this surging, and some that aren't, that the problem ought to be fixable without resorting to this. I'll be doing more drive-testing with my laptop mounted on my bike when I get the next beta load for VDSTS from Techno. The testing that I was doing was on my S3, and I need to do the same test on my Uly to see if the O2 voltage swing is as large. The S3 is DDFI-1, the Uly is DDFI-3, I believe, and I'm sure they've changed/improved the algorithms. Al | ||
| Destroy |
Don't mean to butt in, quick Q, do Buells have catalytic converters? Also FWIW, when I test drove several Buells at the demo days, I easily noticed this surging condition. Very similar feel to some cars when their O2 sensors are getting slow or weak. (Message edited by Destroy on June 20, 2006) | ||
| Al_lighton |
no | ||
| Teeps |
Below is an email reply I received from Warren,in Australia, from the XB Board. I asked him if he was removing the TFI because of problems, this is what he said: I have not had problems with the unit, I was using it with the standard ECM and now have the race ECM in place so just wasn't needing it anymore. They do take quite some time to tune in, I did a lot of testing of settings and found it did help a lot once set right, but be prepared to test and tune a couple of full tanks of fuel - it really needs some patience. Tip for installation is remove right side scoop thing and fit plugs from below by reaching up between frame and engine, much easier. hope this helps, Warren. | ||
| John88030 |
Al, many thanks for posting and I think I understand. On point though, I believe the problem that is most objectionable is below the closed loop area. At light throttle say 15/20 in first the bike acts like it is extremely lean. Slightest throttle movement results in a big change in power delivery. Throttle acts more like an off switch than a "linear" device. There is a lean surge feeling in closed loop but I can live with that. Teeps do you agree, or do we have different problem. | ||
| Teeps |
My problem exactly... for low speed running. I have not noticed a problem in closed loop. Thus my interest in the TFI Jet-Kit. I would buy it (TFI Jet-Kit) and try it, if I could get a satisfaction (return for refund) guarantee. (Message edited by teeps on June 20, 2006) | ||
| Lorazepam |
Mine is at low rpms as you guys describe. It is like a switch is cutting off spark or fuel, and not in a constant manner. Mine has gotten better as I have gotten miles on the bike. I have started letting the bike warm up a bit more before starting out as well. It is definately in the open loop mode where the worst surging occurs. | ||
| Destroy |
Just tossing something in the air here but what about the fuel itself? Lots of different % blends of oxygenated fuel; some areas have no alcohol at all in the gasoline, others up to 15% alcohol. | ||
| Teeps |
Destroy Posted on Tuesday, June 20 Just tossing something in the air here but what about the fuel itself? Lots of different % blends of oxygenated fuel; some areas have no alcohol at all in the gasoline, others up to 15% alcohol. Good point Destroy; but we have no corn in our fuel, here in L.A.... yet. I use Mobil, Union76, or Chevron Premium, which ever is on the way of my ride. |
