CO Settings

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S76

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For those of you, like myself, that can't leave well enough alone, here is a thought to consider.

When the 06 was new it ran like all the rest, OK, but lean. So I did the Barbarian mod and set it at +7 for all cylinders. Notable improvement, but not totaly smooth. So I try +9 and +5 only to find that +7 was the best and I figure that's the best I can do, but it's still not all that smooth.

My original CO settings had a big split. Like 10, 18, 18, 24. Why is this? Maybe because the fuel pressure in the manifold is less at the end by the #4 cylinder and it needs more dwell on the injector? I don't know. But, I figure if +7 helps out the 10 setting on #1 cylinder maybe it takes more than +7 to create the same effect on the +24 of the #4 cylinder?

So just guessing around I set:

#1 @ +7

#2 @ +9

#3 @ +9

#4 @ +10

I've run the bike like this for a few hundred miles and it sure seems to be the smoothest it has ever been, especially at cruise. It seems the foot peg buzz is reduced and the power is up.

IIRC not all bikes had this large of a spread in initial CO settings and for them maybe this does not apply, but for any one that does have a big split like this, my head is convinced it was an improvement.

Maybe someone that has a big CO spread can try this and see if it makes a difference? Only takes a minute and can be easily restored.

 
As always - record your OEM settings and your changed-to settings so you can revert back if needed.

SOMEONE'S dealership didn't do that and now they're stuck getting rivnuts installed and scheduling a session on a EGA system if they want things to work right.

 
well mine where set to 5,18,18,24 and I did +7 to them all, so am I to assume that you set all yours to low numbers or are those the numbers that you added to the original numbers

 
well mine where set to 5,18,18,24 and I did +7 to them all, so am I to assume that you set all yours to low numbers or are those the numbers that you added to the original numbers

If you already have +7 on them all, go back and add:

CYL ADD

#1 0

#2 2

#3 2

#4 3

That is what I did and it seems much better.

Edit: My apologies. Now I see what you are saying. The numbers I originally posted were ADDED to the factory settings.

 
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I don't mean to hijack this thread, but this discussion and others similar to it ask me to raise the question:

If one were to add a Power Commander to the system, then is there still benefit to adjusting the CO settings as is being described, or does that become superfluous?

[[And speaking of the PC, has anyone found a "down-side" to its use using stock pipes (not considering the cost of the unit).]]

thanks

 
I don't mean to hijack this thread, but this discussion and others similar to it ask me to raise the question:
If one were to add a Power Commander to the system, then is there still benefit to adjusting the CO settings as is being described, or does that become superfluous?

[[And speaking of the PC, has anyone found a "down-side" to its use using stock pipes (not considering the cost of the unit).]]

thanks
I really only have two things I am going on for this theory.

1. I think my bike was a little rough.

2. I had a big spread in the factory settings on CO.

Actually, at first I figured maybe the big numbers were too rich. So startin at +7 (above factory settings) on all cylinders, I subtracted 2 points from 2 and 3, and 3 points from #4. Bike imediately ran worse. Bad surging around 3 or 4 K RPMS at light throttle. Definetely lean. So I went the other way and added 2 points to 2 and 3, and 3 points to 4, above the +7 I had already put in. All the while leaving #1 the same, at +7. Noticable difference. It has been like this for a few hundred miles and the MPG indicator is saying 48 if I drive easy, like, with traffic rather than around it.

I guess really the question I have is why aren't all the cylinders the same, or nearly the same. Why is it that the numbers all go up as you move from #1 to #4. Is there reduced fuel pressure in that end of the injector manifold? If so, maybe increasing by +7 is adequate for #1, but maybe not adequate for #4. That is why I tried this to begin with. It seems to have made a positive difference. I was hoping someone else with a big factory split in CO numbers would try to verify.

I would assume the same would apply to a Power Comander. I am not familiar with them though. Can you set individual cylinders or is the MAP the same for all?

It's all fun to me. When I get done fooling with this I'll find something else that isn't broken to work on.

 
Well here in upstate Ny I tried your way but the bike ran worse, but vibration was there just different! I then went back to 5,18,18,21 and subtracted 7 from the base and I must say the bike runs strong and smooth. On the highway at 75mph or so I still get vibes and different frequency. I guess some top gun bar ends will soak up the rest I HOPE. now if I could figure which is the best oil to use!!!!!!!

 
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I think youse guys are nuts!

IMHO, you are swagging at stuff that should NOT be swag'd. And sorry, but I don't trust butt dynos.

If you are going to mess with the CO settings, install rivnuts, get an EGA, and do it properly. That is the ONLY way to truly know what you are actually doing.

 
Well here in upstate Ny I tried your way but the bike ran worse, but vibration was there just different! I then went back to 5,18,18,21 and subtracted 7 from the base and I must say the bike runs strong and smooth. On the highway at 75mph or so I still get vibes and different frequency. I guess some top gun bar ends will soak up the rest I HOPE. now if I could figure which is the best oil to use!!!!!!!

Do I understand correctly, you are running 7 points BELOW factory settings? That is interesting.

 

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