any info on complete exhaust system change

[R1000]

No probs You are never wrong with the factory fuel control system, it works amazingly well even with aftermarket systems. My first impression when adding the PC III (on top of a full R-77 system) was - does it make any good at all...The difference was less then I had wished. The R-77 system did however make a great improvement to me.

 

[Mr Bogus]

My apologies....

As explained above its all relative to the type/style of riding one does! For me however, as an everyday rider, I let the factory system with Yosh pipe do the trick. Not looking to squeeze every last pony out of her and I enjoy the reliability of the factory tune to keep me in check.

I figured that was your meaning.. Also there is a bit of an error in one of the above posts.. the stock ECU with 02 does not maintain a constant 14.5:1 mixture ratio, if that was the case, you would not need much in the way of sensors.. It will modify the A/F ratio relative to the throttle position and engine vacuum.. it can tell you are at low R's hard on the throttle and that the request is for maximum power.. at that point the A/F ratio will drop.. otherwise the motor will buck/backfire or even quit running.. There is NOT any ideal A/F ratio for a motor as this number changes depending on Load and RPM..

Yes you see guys go for a flat A/F curve on the dyno but those are at WOT, not partial throttle settings.. You have no need for 12.5:1 at cruise any more than you want 14.5:1 at WOT...

The factory unit is far superior in fuel management than most any aftermarket solution for street riding.. If you are drag racing that is a different animal entirely.. fixed throttle setting in a very narrow RPM range vs infinite throttle settings at a very wide range of RPM demands..

 

[R1000]

You are right in that the stock fuel control does not always keep the A/F-ratio to 14.5 to 1, which isn’t claimed either. The point I try to forward is that when the bike runs on light load on 12.5 to 1 instead of 14.5 to 1 (which it is stock on light load) the engine will respond faster and stronger when twisting the throttle. The difference in feeling and fork stretch is significant.

 

[EarlyBird]

12.5:1 to 13.2:1 airfuel ratio is for best hp and torque. The 14.5:1 airfuel ratio is for best emissions and part economy. You are right with it being snappier with an airfuel ratio of 12.5 which is best power which comes at the cost of fuel mileage. I have a full R-77 system and love it. Lost 35lbs. on the bike and gained more mid range. I know a tune would help it out more. But loosing the O2 sensor for 90% street riding isnt for me!

 

[Stealth08]

I am new here so please no flaming when I ask a question that you might already have been asked, but... Has anyone run a Yoshimura R77 full system with NO powercommander or bazzaz fi unit and WITH the HealTech X-TRE installed? I am considering a Yoshimura system for the first time ever since it can use the factory O2 sensor and stock computer. I have always, since 99 used Akrapovic exhausts and I am looking at switching because of this sensor plug. I am a street rider and like to take trips also, so having the most power with reliability in a variety of conditions would be a must. I haven't heard of anyone on here talking about a full system with stock computer and X-TRE. Let me know if anyone has this combo. and how it feels versus stock. Thanks for any info.

 

[zx9r]

I have that exact setup. I have had no problems. The X-tre was awesome. I observe a noticable gain after I installed it. Im about to install a BMC filter and PCIII. Curious to see how that works out for me.

 

[bigbusabigbusa]

Posted via Mobile Device

 

[bigbusabigbusa]

correct if i am wrong but my thinking is if the tre puts the 5th gear map it richens the fuel mixture so if you put a full exhuast on we tend to believe the bike will run lean but the tre should compensate for this. am i anywhere close or i as dumb as i think i am. thanks
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[Stealth08]

That is interesting. I figured the X-TRE would give you a decent gain but what gain would you get from the yoshimura pipe by itself. Is it worth the money or should someone go full system and powercommander of another brand? I would be interested if anyone has any dyno info on just the x-tre or the yoshimura full system and possibly both together without PCIII. If the stock computer would do well with an x-tre and yoshi full system and not much of any gain after that for a Powercommander then I would have my mind made up. I want the most power but I am getting the idea that the PCIII is only worth a couple ponies and only after hundreds of dollars of tuning on a dyno. Anyone dyno their bikes without powercommander and these other two parts? I know somone on here must have the info I am looking for. Thanks lease:

 

[BA BUSA]

Gen2 Busa + Yosh + PCIII = $$$ NOT well spent

 

[Stealth08]

I figured this but what makes decent power on this bike? I have had great luck and more power out of Akarapovic on R1's in the past and I am new to Hayabusas in general. I like the Brock's Alien head but keep hearing about how darn loud they are on the highway. What are you using on your bike BA Busa?

 

[BA BUSA]

My '08 is stock, my '03...which I use on the track (road course) has a Akro Evo, PC3R, and a custom map.

 

[Stealth08]

Yes, If only Akrapovic made an Evo system for the 08 I would love that. But all they make now is the race system, although it is still my favorite pipe. Just didn't want to have to spend a small fortune plus powercommander. Best place to get Powercommanders cheap. I found 58cycle.com to be best for pipes.

 

[BA BUSA]

Yes, If only Akrapovic made an Evo system for the 08 I would love that. But all they make now is the race system, although it is still my favorite pipe. Just didn't want to have to spend a small fortune plus powercommander. Best place to get Powercommanders cheap. I found 58cycle.com to be best for pipes.

I want a EVO for the '08...but they don't have it out yet

 

[Stealth08]

Anyone heard if Akrapovic is going to make and Evo full system for the 08 Busa? Is it a sure thing, just not out yet? lease:lease: