New Busa, New Exhaust Question


Im sure I'm "that guy" asking the same question that's been asked thousands of times, but I have a few questions, and I was hoping that possibly some experts/sponsors could chime in.

I picked up a 13 busa with very low miles, all stock, unmolested. As a former Toyota mechanic and Toyota school grad, I appreciate good engineering. First and foremost I'm seeking to maintain long-term reliability, as opposed to a building a racer. Although I can r&r just fine, I'm certainly no engineer with their depth of knowledge.

I also realize that EPA and noise requirements potentially muzzle these bikes from the drawing boards. That said I just ordered a full Yosh R55, to shave some weight, get some bark, and trim up the girth. I certainly don't want to lose performance anywhere.

Yoshimura states on their site that the "race series" category of systems (which R55 falls in) are designed with power increases and performance at the fore-front, to paraphrase.

Sorry to drag on, but if that's the case, does anyone know if their R&D is based on bone-stock examples of bikes, including mapping? Logic tells me yes, as otherwise too many variables would muddy results...

I ask because I'm extremely hesitant to undermine a team of Suzuki engineers and let an unknown or unqualified entity have at my ECU. I don't want my bike to run like crap, and certainly don't want a hot tune, leaning stuff out , that'll kill my engine prematurely.

Can I expect power loss anywhere in the powerband, just throwing this system on, and calling it good?
Your question is valid in that it seems you are not wanting to be presumptuous by disregarding the "team of engineers" by reprogramming their mapping BUT keep in mind they are working under strict constraints that leave even a stock engine running at much less than optimum setting.
In other words your stock motor would run MUCH smoother and with more torque with the restrictions tuned out of it even before the exhaust improvement. Your Yosh will run "okay" without tuning although with some annoying popping sounds, but to get the full benefit of the install (and probably run cooler too) get it remapped.
I say all this to clear up why we all say get it mapped even though Yoshumira says you don't absolutely "have" to.
Just to throw this out there . A power commander 5 will set you back 350 bucks new and its a piggy back fuel module . They are / were great for bikes with ecus you could not flash . The price for a flash only is less than 100 bucks . Tune / flash 350 to 500 bucks . Last option is way to go
Im in Las Vegas and don't know many people here to ask, to find who's a good tuner, and who's not. Anyone happen to be from here or nearby? If I was to send my ECU to Frank at Powerhouse for a flash, a tune would still be required after? Thanks for the replies.
Frank does great work ! A flash will help , but largest gain will not be had till a full tune .
Just a F Y I I'm running a full exhaust / filter with just a flash from boosted cycle performance here in Houston Tx. Now I mostly TOUR on my bird so
I'm by no means racing or pushing the ragged edge to damage motor by being a tad lean . Factory
Is Very LEAN .
I plan on a full tune in early fall as air will be better for when I tend to ride the most miles .
Summer here I ride 1000 or less miles , but fall , winter , spring 10,000 to 15,000
Nice to know c10, a little reassuring..I'm going to try to get an appt. For a baseline dyno this week I suppose.

Like you, I bought this bike to use mainly as a touring bike (kept my tl1000r), but it would be a bold-faced lie to say I won't commit felonies on it, when the opportunity presents. I was actually considering a Goldwing, but steered away from that because I am in fact heterosexual and under 40... and the Busa would be easier to work on and more fun for around town romps which I'll likely use it for more often than 2-up riding.

So order of operations to confirm:

-baseline dyno for reference
-install exhaust
-ecu flash
-dyno tune

Will I lose any instrument indicators, functions or features upon flash or dyno tuning? Mileage will still read accurate, etc?
Save your funds as a base line is dyno dependent , and going to show close or same as all the magazines said for a gen 2 bird from 2008 to current 17 model about 172 hp at the rear wheel . My Flash did away with the A / B / C MODE showing . Everything else was unchanged . Others say they still have A / B / C MODE so not sure what was selected in the ECU to change this from others .
Millage only changes from a gearing change with out use of a speedo healer . I run a 19 tooth front with a 190/55 out back and speed now matchs GPS perfect , but the odometer is now off by 4.7 miles per every 100 miles ridden compared to a GPS . Before the Odometer matched GPS mileage
Stored mileage stays no issue . A/B/C matters not to me as rider mode is in the right hand not a button . I would like to find a use for them now though like turning something on / off . Rob at boosted cycle performance did my flash . However I wonder if he is OK as no answer to his phone number for last few months .
Thanks again C10.

If anybody read and was curious on the answer from Yoshimura, I got an email reply from a Yoshimura customer service rep with the answer that the systems are in fact designed and performance tested on stock motorcycles w/ stock mapping, and he provided a sample dyno sheet upon request for the R55 system, which in this application yielded a peak hp gain of 8 hp, and 3 ft lbs, in stock trim, but what looks to be pretty desirable power and torque curves, which stay above stock levelsfrom like 3k rpm and up.

One of the reasons I was curious, was because of the Gen ii's o2 sensor, and I'm assuming some sort of MAF sensor or intake air meter which like a modern automobile can compensate to a degree with no modifications to the ecu necessary, unless parameters and duty cycles are maxed out, or every last bit of power is hoped to be wrangled... not my goal, however.

For me and my purposes I'd assume keep it as close to stock as possible however, from this point, with the possible addition of a mail-in, mild re-flash- if i can retain my stock modes... Should have the weight shaved, the tone, heat reduction for my passenger and i, finish, size and profile I wanted though.

Thanks again
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What you heard from Yoshimura was the company mantra as required by law. California has some of the strictest emission requirements in the entire country, forcing companies to comply to the new rules. Dynojet does it by selling "EX" powercommanders (in California) that prevent you from altering the fueling in certain areas. In order to stay in business, exhaust manufacturers are required to state that their systems do not require remapping. We know better. The stock O2 on your bike also has emissions in mind - not performance or throttle response - by keeping the closed loop in the 14.7 area. Too lean, but good for the country.

It actually goes way deeper than what is being discussed here - at last year's SEMA conference, the buzz was about whether or not aftermarket performance companies had any future. Our glorious government was pushing to shut them down - in fact, to shut down anyone who "changed" the way a vehicle came off the production line. No exhausts, no cams, no ported heads, no nitrous - the list goes on and on. Anything that required changing the fueling would have been illegal. They even wanted this to apply to off road, closed race courses as well. Just imagine all those Nascar guys going round and round with stock mufflers.

I am not touching on all of it here, but the law did not pass. But there are ramifications going forward. Everything performance related is now for "off road" use only, and until such time when they require motorcycles exhausts to pass the sniff test, we are at liberty to do what we want, with clarification.

The bottom line is that the OP should get his ecu flashed and also get a PCV and have his bike custom dyno mapped by someone with a good reputation. He will get the most out of his ride, the best throttle response and good power overall, IMO.
So Frank, you recommend a PC over editing the factory ECU? Because there's more aptitude by dyno tuners nationwide, or it's advantageous by design to me?
So Frank, you recommend a PC over editing the factory ECU? Because there's more aptitude by dyno tuners nationwide, or it's advantageous by design to me?

By design, we are talking apples and oranges here. Just because you can change the fueling through the ecu does not mean that you should. A powercommander in the right hands will be more precise than trying to accomplish the same thing through the ecu, and a good tuner will spend way less time making a custom map with the PC. So I don't recommend one over the other, I recommend both. Use your ecu for de-restricting, raising the rev limiter, disabling the top speed limiter, changing fan temps, etc. Yes, you can do more with the ecu than you can with the PC. The PC only does one thing: fuel mapping, but it does it better and easier and it is more about the software than it is about the hardware. I have worked with many different platforms including fuel mapping ecus, so I have a little exposure here. You can be on the dyno for six hours, or for less than an hour. That's one big difference right there. Another big issue has to do with differences in resolution, software and operating parameters. It is easy to unknowingly complicate things.
Thanks man. I noticed today a "Power Commander FC" that plugs in without splicing or anything. If I'm understanding correctly this would satisfy my needs, as it provides generic maps, and the ability to custom map, differing from the PCV in function, only in that accessories can't be used? Any opinion on these?
From the dynojet website:

"Power Commander Fuel Controller (PCFC)

Product Overview
The Power Commander FC is a new plug-n-play fuel management device pre-programmed with Make/ Model specific maps. In addition the Power Commander FC has the added ability to modify or change these maps on the fly without a computer.

Users can literally select between a Power Commander FC Map, custom-built maps, or even fine tune low, mid or high rpm ranges while sitting on the bike and without plugging into a computer. Standard +/- 10% increments from selected map settings, different ranges are available using the supplied Control Center software.

Users can also load up to 10 of their personally built Power Maps into the Power Commander FC and select between them while in the saddle - eliminating the need to "re-boot" with the computer every time a new map is desired.

PCFC Features
  • Uses OEM style connectors and high quality wiring harnesses
  • Small, lightweight and easy-to-fit on the bike
  • Pre-programmed with PCFC Power Maps specific to make, model
  • No computer necessary for modifying fuel management
  • Fully adjustable computer compatibility for ultimate tuning and personalization
  • Software is compatible with Power Commander, so you can download Power Commander maps to the PCFC
  • Integrated O2 Optimizer where Applicable
  • +250 / -100 fuel change. Enough adjustment to cover almost all modifications
  • Enhanced “accel pump” utility (increased adjustment and sensitivity ranges). When you need to adjust your fuel curve for quick throttle inputs."

? So the maps are different on the FC from a PCV, they're not the same?? I'm not saying doing this in lieu of a dyno tune, just instead of hard wiring a pcv...

This all sucks. I might just pay the restocking fee and bail. I refuse to cut into my harness on this one.
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You wouldn't need to cut into any harness with either product. The PCFC is not adjustable in the same way a PCV is. If you just want to throw some generic map in and you don't care, the FC will do that for you.
Then pcv it is, I was under the wrong impression. Traveling from Vegas at 2000, to Utah at 6600, and CA at sea level, should I mess with Autotune? I heard that it is "laggy"? Thanks for the help.