AttakDog
TY 4 Stroke Junkie
Can someone tell me how to adjust the CO settings on a 09 nytro? I have a hesitation that I want to try to fix by adjusting the CO. Thanks!
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- 2014 Yamaha SR Viper LTX, 2014 Yamaha SR Viper RTX SE, 2015 Yamaha SR Viper MTX SE 162 (turbo), 2015 Yamaha SR Viper MTX SE 153
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In the nose of the sled there is a single female white connector maybe 3" back from the ECU. This connector currently has a "cap" in it. You remove the "cap" and hook a wire to it and ground it to the chassis. Then you will want to go into Diagnostic mode.
To enter Diagnostic mode:
- With the key and kill switch off, press and hold both "Select and Reset" buttons then power up the gauge by turning both the key and kill switch on.
- Wait 8 seconds and the gauge will go blank except for "DI" in the display.
- Press "Select" to toggle between "DI" and "C0", Select "C0". (If it doesn't go to "CO" then you do not have the wire ground properly).
- Press and hold both "Select and Reset" 3 seconds
- Gauge will display "C:01", (this is where you select which cylinder you want to adjust)
- Press and hold "Select and Reset" 3 seconds and 0 should appear in the odometer section
- Press "Select" to increase the number (richer), "Reset" to decrease the number (leaner)
- Example: (10 would be richer) (-10 would be leaner)
- Press both "Select and reset" to chose C:02 and adjust the same as above (must do this for each cylinder)
To enter Diagnostic mode:
- With the key and kill switch off, press and hold both "Select and Reset" buttons then power up the gauge by turning both the key and kill switch on.
- Wait 8 seconds and the gauge will go blank except for "DI" in the display.
- Press "Select" to toggle between "DI" and "C0", Select "C0". (If it doesn't go to "CO" then you do not have the wire ground properly).
- Press and hold both "Select and Reset" 3 seconds
- Gauge will display "C:01", (this is where you select which cylinder you want to adjust)
- Press and hold "Select and Reset" 3 seconds and 0 should appear in the odometer section
- Press "Select" to increase the number (richer), "Reset" to decrease the number (leaner)
- Example: (10 would be richer) (-10 would be leaner)
- Press both "Select and reset" to chose C:02 and adjust the same as above (must do this for each cylinder)
AttakDog
TY 4 Stroke Junkie
Thanks Allen I am going to try 3+ to start
nytroman20
Expert
When cruising at about 35-40 mph theres a popping sound when i gun it.... would adjusting this help the hesitation sound?
nate007
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There has been a few threads since the Nytro's have come out about the popping sounds, especially when adding exhaust.
From my understanding, some of it is normal, and not usually noticed until modding your machine. I know Mr.Sled has looked into this with a couple of Yamaha techs I believe he said his findings were that it is just a quirk in the programming due to the 120* firing order of the 3 cyl sleds? Someone chime in here if I'm wrong, I'm just typing from memory approximately 3 seasons old..
I'd be relatively sure a control box and some of the other popular mods will help...
From my understanding, some of it is normal, and not usually noticed until modding your machine. I know Mr.Sled has looked into this with a couple of Yamaha techs I believe he said his findings were that it is just a quirk in the programming due to the 120* firing order of the 3 cyl sleds? Someone chime in here if I'm wrong, I'm just typing from memory approximately 3 seasons old..
I'd be relatively sure a control box and some of the other popular mods will help...
ericmichael
Expert
nytroman20 said:
Are you sure its not the rev limiter??Last week I took the instructions from this thread and changed my nytro CO setting from stock 0 to +2 and the low end mis is gone...I love it.
AttakDog
TY 4 Stroke Junkie
I went to a +5 and its a bit too much. I am going to back it down to +3. It got rid of the small hesitation but its a little to fat off idle. It does seem to pull a lot harder than at zero though. Alan said every sled is a little different and you just need to experiment
AttakDog
TY 4 Stroke Junkie
Oh yeah just a side note....the sled ran 10-15 degrees cooler on the digital temp gauge in nearly the same conditions and temps. Obvious because of adding more fuel but I didn't expect that large of a change
nytroman20
Expert
Its not the rev limiter because its only when cruising at 40 then gunning it....I opened my exhaust so maybe thats why im hearing it..... I already adjusted the CO to +2 and it still kinda does it...it also seems to pull a little harder..im thinking of putting the air filter kit thats on this site..the K&n's...would i need the fuel programmer if i did this? thanks guys!
raginyamaha
TY 4 Stroke Master
if u opened the exhaust too, fuel programmer would be needed.
HRD2PLZ
Expert
Is there any danger to the engine involved in adjusting this? Is there any possibilty making these adjustments may void the warranty?
Are you guys doing this with just stock sleds? ive got full exhaust, k and n filters, clutching, and programmer. would you guys suggest changing this to like +2?
ericmichael
Expert
2008FxNytro said:
The best way to tell is check your plugs...but depending on your elevation it could be rich or lean...I'm 0-3000ft of elevation so mine was running lean with the stock setting of 0. I increased to +2 and the mis is gone.
2008FxNytro said:
You have a programmer, why would you mess with the CO on the sled? Just make any and all changes with the programmer.
I kinda figured i could. didnt know exactly what changing the CO was doing. I can add or subtract fuel with the programmer
