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As Jaxon/Tabasco pointed out, you are going to get lots of views from both sides of the fence, but in the end it is all about what *YOU* want, and what you want to achieve with the bike.
That said, you asked, so here's what i did, and why...
I went with the ECUnleashed re-flash. IMHO, it is a much more elegant and simple solution to what I was looking for. I wanted to get the fueling smoother and cleaner down low, and better throttle response, and certainly remove any Yamaha emissions/noise nanny restriction maps in any of the gears... And yes, USA models have those restrictions, too. Many were doing the jumper CO-mod, airscrew fiddling, etc. to try and get rid of the occasional low-speed stumble and inconsistent fueling at ultra-low RPM, but both of those just seemed like band-aids to me. I knew from various discussions with those in the know that the re-flash would solve this issue better than most. After all, a re-flash is an opportunity to re-map the fueling and other parameters to whatever is optimal for the engine all across the rev range and under any load condition. The airscrew and CO-mod can only address a limited part of the operating range, so that seemed like only a partial fix - at least to get an optimal result.
The other great thing about the ECUnleashed re-flash is that it can done to match any mods you have to the engine, and even help it a ton stock (more on that in a moment). And better yet, if you make mods later you can have the ECU re-flashed (at a much lower cost) to take those mods into effect.
I had my personal ECUnleashed re-flash done by AF-1 Racing in New Braunfels, TX, and at the time I was also planning to install a set of Arrow header pipes so I could eliminate the catalytic converter, though I wanted to keep the stock muffler (I like *Q-U-I-E-T* motorcycles, but I hate catalytic converters), and so I had the re-flash optimized for such a set-up. AF-1 ordered up my Arrow header pipes and I picked them up the day I went in to have my ECU re-flashed. Brought everything home and installed the ECU, but with the stock header pipes...
To say I was *HAPPY* is certainly an understatement. It performed better than I originally thought it might. When I went into it I didn't have any rose-colored glasses on about what the re-flash would do. Some were looking for *HUGE* power gains, or something that transformed the bike into some sort of R-1 beater. I knew it couldn't do that, and had no illusions about it. They don't advertise it that way, and nowhere does anyone who does the re-flashes claims anything like huge power gains... Just modest ones and the removal of any mapping restrictions in the ECU.
However, my re-flash has performed so well with the bike stock I have not even put the Arrow headers yet. The best part, to me in particular, is the improvement in low-speed, low-rev fueling. I can idle around with the clutch out like I'm on a trials bike... Something the stock ECU programming wouldn't allow. Now there are no bucks, stumbles, snatching, or jerkiness at low speeds, and you can literally slip the clutch out at idle and get rolling. The improvement leaving stop lights and signs is so dramatically improved that it's hard to describe. And that's the kind of improvement you use not just every day, but every time you come to a stop. From there on up it just gets better... Smooth, linear, wonderfully usable power. The Super Tenere has a pretty damn nice torque curve and power delivery stock. The ECUnleashed re-flash just makes it better, all across the board. From idle to redline it's like a locomotive, pulling at every RPM in any gear, without stumble or hesitation, and with authority. Pure torque... Just like I like.
You might ask why I didn't go the PC-V route... Well, I've had Powercommanders before, and while they have their place, and those types of "add-on fuelers" were once the best game in town, if you look at the problem more closely and objectively you may come to the same conclusion that I did - they are nothing more than an external band-aid to try and mimic re-mapping the actual ECU. IN other words, they attempt to literally do a re-flash, only without actually re-programming the ECU. What they do is try to *trick* the ECU into delivering different fuel amounts than it actually wants to. These "fuelers" do this by various methods, but it is all actually done externally. So, this means that if the "fueler", or its wiring, or the installation fails, or has issues, then you suddenly lose its benefits... Something that can't happen with a true re-flash. Just always seemed to me to go to try and cure the disease rather than putting on a band-aid.
For me, I believe in the KISS principle - Keep It Simple Stupid. A lot of years in the trenches of professional racing, both on two- and four-wheels, taught me the simplest, most robust solution with the fewest parts was usually the best way to go. I like reliability. I like it a *LOT*. And to me anything added on only serves to reduce reliability - i.e. the more things there are to fail, the more likely one of them will.
I've had Powercommanders on a number of bikes, and other brand "fuelers" on another couple of bikes. They're great - when they work. But have a problem, and it's hell tracking down whether it's the actually Powercommander, if the maps have gotten scrambled, the wiring, or what. It is frustrating as hell, and can have you pulling your hair out. Like I said, in their day these "fuelers" were definitely the answer, but that's only because for a long time they were the only game in town. I know that when I was in Indy Car racing you never saw anything like a PC-V. If you wanted to change the fueling, or other parameters, out came the laptop and the ECU got re-programmed. Simple as that, and believe me about two things... Reliability is everything in that game, righ tbehind horsepower... And if some add-on device could aid power then they would have it. But logic will tell you that re-mapping the ECU is getting to the root of the issue.
In closing I will mention one last advantage of the ECUnleashed re-flash... It runs "open-loop" at all times, so you can toss the Lambda/O2 sensors. This gets rid of one more electronic component that can fail, so that even improves operating reliability. Take it from someone who has had O2 sensors fail, and when they do they always pick the most inopportune times!
Understand, I think DynoJet makes a fine product with the Powercommander line-up, and I have nothing against them in any way. It's just that to me they will one day be as antiquated and odd as people see carbs now. ECU-remapping has been the norm in the four-wheel world for years, and you rarely, if ever, see any "add-on" boxes there. Nope, instead you now buy "tuners" that re-map the ECU. That's the way motorcycles will be going, and many already have... Even the OEM manufacturers. Just witness the current crop of MX bikes from the Japanese, KTM, etc.
Just my two centavos... YMMV.
Dallara
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