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No but now that you have mentioned it, does this BB have an 02 sensor from the factory?
If so then that's your problem the bike is running lean. Not dangerously so but annoyingly so.
 

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Octane increase will only aggravate it. Higher octane burns slower.
Interesting subject fuel. octane its just a part of its makeup if you look at what goes into fuel you would be a bit more selective, If i have a bike that idles rough its probably just the shit they put in the fuel, i upgrade the fuel octane first, if the problem persists change the plugs and usually the problem goes away i am currently running BP98 on my busa and it absolutely purrs gear changes smooth as silk and wont use anything else.
Also classic cars guys have the same issues they swear by trying different octane fuels that suits their engines they get bigger results some of the 70s cars love higher octane it just whats in the fuel that makes an engine either love it or hate it
 

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Agree with what your saying. But his symptoms are.
However, they seem to have impacted the low to mid range response, and caused it to stutter at part throttle. It has a K&N filter too.
Adding to this.
will I need to blank off the existing o2 sensor for the PC V to work with uploaded maps.
So deducing from the above and what I have experienced from an 03 I had here.
So here is my deduction from experience. We know the BB is in the edge of balance on the carbed versions. If you change on side of the system exhaust its happy. Remove the air shields or change out the air filter though and it reacts as described above.
The FI's are more forgiving and run well. But they can still improve with a tune tweak.
The exception to this rule is the 02 versions of the BB. It was setup to pass a more stringent emissions standard. To do this they leaned the system out. And use the sensor to keep it trimmed. The issue this creates is a lean stutter when you gently roll in throttle. Another condition it will exhibit is a surge at steady state cruising.
 

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So, will I need to blank off the existing o2 sensor for the PC V to work with uploaded maps? I'm sure I will work it all out so being lazy re going through old posts.
You can leave the sensor in until you get a plug.
But the biggest thing is you'll need a delete plug installed in the harness. Otherwise any changes you try to implement, the system will try reverse.
They sell it on there website.
 

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Hello from Australia!
I just fitted 14" Delkovic slip-ons to my Bird which I am really happy with re quality, original look and sound. However, they seem to have impacted the low to mid range response, and caused it to stutter at part throttle. It has a K&N filter too. I assume the flow increase with no Cats means the ECU can;t correct the fuel enough?
Appreciate a PC III or V would be the go, however they seem to be out of stock, plus I have read a few posts re issues with them. Its my daily ride to work, so it needs to be reliable. Thinking of trying a Memjet which I know is a work around, but thinking it might just improve its performance enough.
Any thoughts?
Regards
Jason View attachment 130898
Hi,where do you live?
I got a POWER commander 3 if you need it.
I run one on mine with staintunes ,K&N filter andgoes great.
Never had any worries and unlike the pc5 you can tune them manually as well.
 

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Hello from Australia!
I just fitted 14" Delkovic slip-ons to my Bird which I am really happy with re quality, original look and sound. However, they seem to have impacted the low to mid range response, and caused it to stutter at part throttle. It has a K&N filter too. I assume the flow increase with no Cats means the ECU can;t correct the fuel enough?
Appreciate a PC III or V would be the go, however they seem to be out of stock, plus I have read a few posts re issues with them. Its my daily ride to work, so it needs to be reliable. Thinking of trying a Memjet which I know is a work around, but thinking it might just improve its performance enough.
Any thoughts?
Regards
Jason View attachment 130898
Hello fellow fighter pilot! Have a simple request! Could you please take a picture of yur pipes from the rear? Would like to see them from that perspective... be greatly appreciated! Great forum and even greater people! Welcome aboard and ride safe!
 

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Discussion Starter #27
Hello fellow fighter pilot! Have a simple request! Could you please take a picture of yur pipes from the rear? Would like to see them from that perspective... be greatly appreciated! Great forum and even greater people! Welcome aboard and ride safe!
Will do.
 

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Discussion Starter #28
You can leave the sensor in until you get a plug.
But the biggest thing is you'll need a delete plug installed in the harness. Otherwise any changes you try to implement, the system will try reverse.
They sell it on there website.
Thanks. Going back a bit you asked about the model. Its an Australian 01 which I believe is the same as the Euro versions with the O2 sensor as standard.
I ordered a delete plug. I also pulled the O2 sensor out of my race car on the weekend and poked it into the Birds exhaust. Was idling cold at 12.8:1 which I thought was a bit lean? Tempted to take the air/fuel logger out of the car and tape it on the bike to see what its doing. Could be useful when trying different maps in the PC V?
 

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12.8 is very fat. 14.7 is stitch. Anything above that is lean. Anything below is fat. 12.5 to 12.8 is ideal when your really loading it like pinning the throttle and hammering gears for max acceleration kind of loading it. But that's at idle which the PC won'ttouch unless you tell it too. You want to see 13.8. Just to be clear the bike was at temp correct?
 

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Discussion Starter #30
12.8 is very fat. 14.7 is stitch. Anything above that is lean. Anything below is fat. 12.5 to 12.8 is ideal when your really loading it like pinning the throttle and hammering gears for max acceleration kind of loading it. But that's at idle which the PC won'ttouch unless you tell it too. You want to see 13.8. Just to be clear the bike was at temp correct?
Sorry - meant rich and said lean :(. Engine was cold. Probably not much of a test. Will just wait for PCV then start getting serious.
 

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Yes betting that's why you saw those numbers. It's what I see here on cold day start and warm up.
 

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Hello from Australia!
I just fitted 14" Delkovic slip-ons to my Bird which I am really happy with re quality, original look and sound. However, they seem to have impacted the low to mid range response, and caused it to stutter at part throttle. It has a K&N filter too. I assume the flow increase with no Cats means the ECU can;t correct the fuel enough?
Appreciate a PC III or V would be the go, however they seem to be out of stock, plus I have read a few posts re issues with them. Its my daily ride to work, so it needs to be reliable. Thinking of trying a Memjet which I know is a work around, but thinking it might just improve its performance enough.
Any thoughts?
Regards
Jason View attachment 130898
 

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Discussion Starter #35
You have gotten rid of the resonance chamber .The standard exhaust will flow as much as the new one at those rev's ,my two bob's worth ! I just run a 27mm (?) Hole saw down through those two baffles in the stock muffler ,runs well and more top end.
Afternoon Squid,
Not sure exactly what you mean. The mufflers still have the baffles installed, and I thought they still had a chamber around them?
My experience with race cars has shown that various mufflers can create more power, but savage mid range torque. That may be the case here.
Will be interested to try the PC V before going back looking at the exhaust.
Cheers
Jason
 

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Thank you! Love the look of the pipes and probably sounds amazing BUT I'd be stopped in a heart beat with "Open" end exhaust here in my city... Again thank you.
 

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Discussion Starter #37
Update - Fitted the O2 sensor bypass plug today. The result was I have my old bike back. The part throttle stutter is all but gone, it idles better, and has far better response. The mid range is still a a bit flat but its a nicer bike. I think many people would just leave it like that, however I can see the PC V will only make it better again.
 

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Great to hear!
 

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Discussion Starter #39
Another update - Power Commander V now installed. Very easy installation being just a plug in.
The first map I downloaded was for a Two Brothers slip on, and absolutely terrible. Massive mid range flat spot and slow in the top end.
I then uploaded the one for Euro model with Yoshi's which was heaps better at 10-30% throttle, but terrible with full throttle and high RPM.
Next step is to pull the Air Fuel logger from my race car and patch that in using the original 02 location.
Ultimately it needs to go on a dyno, however interested to see what its doing on the road first. An autotune module is also tempting....
 

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I'll be the 1st to recommend it. Makes tuning very easy and fast.
 
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