A few questions regarding exhausts/tuning

LastBusa

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Hello and thanks in advance for any input/responses.

1. Is there any reason why the stock 02 sensor installed in an aftermarket pipe wouldn't enable the ECU to adequately compensate for the increased flow?

2. Why is it a good idea to disable all that the 02 sensor enables the ECU to do?

3. Why wouldn't it be advantageous to have the 02 sensor connected even with a pc/bazzaz type device? Wouldn't it actually improve upon what the pc/bazzaz type device does when conditions change like if the temperature is 40 degrees colder than the day it was tuned or if you take a ride up into higher or lower elevations than where it was tuned?

4. Do any of the current 4-2-1 exhausts (Akro, Brock's) have an 02 sensor bung?

Contributing details...

I've been through the pipe/tuning thing with a few previous busas (details below if interested). For this go around, I want to keep it simple. I want an excellent quality, light weight, nice looking, 4-2-1 exhaust, that is deeper and somewhat louder than stock. Since I'm spending $1200 plus, it needs to add noticeable performance but I could care less about a few peak hp one way or the other. I'd like to avoid the hassle of dyno tuning if possible.

I had a Sato pipe with Dennis Clanton's airbox mod and a PC2 on my '00. I had a bung welded in and actually tuned by marking throttle positions on the throttle based on the PC2 and monitoring air/fuel with a video camera pointed at the tach and a Halmeter (and advice from the suzukihayabusa site back then). Maybe not as good as a quality custom tune and certainly not the safest way to tune, but I was quite happy with how my bike ran and especially with what the A/F looked like on a dyno. Although interesting and fun, it took me an entire season to tune this way.

I had an Akrapovic Evolution on my '04 with a PC3USB that was tuned on a dyno. I loved the pipe/sound. It felt more powerful than stock. It ran well but got considerably worse gas mileage. It also had a slight stumble in a few low rpm spots which was never a problem during normal riding but an aggrivation in traffic and slow around town riding. Bumping the 'Low' manual adjustment down corrected the problem for the most part but left me feeling like the dyno tuning (at least in this case) was a waste of my money. I ended up not running it without the manual adjustments in fear of running it too lean. After a while, I automatically stayed a gear higher around town but it always bothered me that I had to change how I rode the bike to compensate for what I thought dyno-tuning would prevent and/orcorrect.
 
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I am running an Akrapovic 4-2-1 on my 09 with no tune, just swapped out the complete system. Still gets the same gas mileage (39mpg avg GPS calibrated) Smooth through out all TP and RPMS pulls harder, plugs look great, light brown coating on the inner part of the tail pipe, power increase went from lifting at 7500 to 5500 with a 245lbs rider.
I dont think I am going to miss with the ECU or buy a PCV, I love the way the bike feels now and the weight loss makes the bike handle so much better.
 
take it back and have them fix it.

I think you're referring to the '04 which I no longer have. Don't get me wrong, it wasn't unbearable, it just wasn't perfect. I thought i brought it to someone that knew what they were doing and "worked on busas all the time". He boasted about how many pulls he did and how happy I was going to be. Left me with the feeling that it was his best work. The gen 1 had been out for 6 plus years at that time. If he didn't have it figured out by then, another shot at mine wasn't going to help.

I know your reputation as a tuner. I don't have tuners at your level of expertise around here anymore which is why I am trying to avoid any tuning at all if at all possible.
 
I am running an Akrapovic 4-2-1 on my 09 with no tune, just swapped out the complete system. Still gets the same gas mileage (39mpg avg GPS calibrated) Smooth through out all TP and RPMS pulls harder, plugs look great, light brown coating on the inner part of the tail pipe, power increase went from lifting at 7500 to 5500 with a 245lbs rider.
I dont think I am going to miss with the ECU or buy a PCV, I love the way the bike feels now and the weight loss makes the bike handle so much better.

I read your recent thread and was going to ask questions within it but didn't want to thread jack so I started this one.

Does your Akrapovic have a bung that will accept the stock 02 sensor?
Did you just do what was necessary to eliminate it?
Does it run the same regardless of altitude, temp, or humidity?
 
reason being the o2 sensor on a stock busa is a narrow band, the aftermarkets have a wide band bung usually.

the stock ecu / non flashed will look at the reading as hi, low, or in range as a saftey measurement to make adjustments.

the narrowband (stock unit) is useful for the portions of throttle positions that a bazazz or power commander does not touch, unlike flashing the ecu. your pre 11 % throttle positions are not touched by piggy back units.
 
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