07 apex rpm's very low and stalls when warm on idle

[WinderFab]

Apex/Attak Fuel Adjustment Process
By: LeadDog



Apex C0 Fuel Adjust:
- Install a wire (or paperclip) from ground to the pale green wire in the connector on the left of the delta box. This wire has no mating wire in the male connector and only needs to be grounded to the Delta Box.




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".
- 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)

You will want to go RICHER (positive numbers). Generally up 10 will be enough to get past any hesitation or stumble you may run into.

 

[Trailblazergt]

Thanks for the quick reply Fabio

 

[black knight]

pardon my last post gents,
I went Leaner (-12) not richer
i said i went richer at -12

 

[JROCK]

I rode this weekend at -10 still have cold start stumble but does not fall below 1400 when it does. Idle is rock solid 1600 rpm very crisp getting better gas mileage. I will check fuel pressure in the off season but sled was too rich at 0. Maybe as they break in they need less fuel at idle. 11500 km on sled.

 

[black knight]

Started it this afternoon. Still a rumble for a couple seconds off the start,
it idle up to 2000rpm then down to 1500rpm for 10-15 secs then
slowly back up to 2000rpm red light turns off and idle eventually
stays at around 1600-1700rpm.after blipping it a hole bunch.Solid
Before it would idle up to 2200rpm then would have to keep my hand on the
throttle just enough to keep it running until it was warm enough to hold at
2000rpm it would always try and snuff itself out within the first 30-45 sec slowly
choking itself down past 800rpm.

would like to find out whats causing the rumbble at startup.

Whats the leanest anyone has dropped one of these?

 

[GUKROKIT]

I would think most of you would be due for a spark plug change since all the stalling ,running rich. Once you lean out the idle mixture you still have your carboned up plugs in there. Mine were pretty nasty. As I said on page 1 all I had to do was set all mine to -5 ,Idled perfect once i took out the carbon fouled plugs.

 

[Grunter]

It's official - like most have reported the C0 adjustment is working very well indeed!
I've got the Ulmer Airbox mod and I went from 15 to 8 and this has done the trick...(about 95% anyway)..
May have to fine tune a bit more...
Mine now idles at 1600rpm..
But if I let it idle for like 20 minutes I can still get it go to 1300...
If I give er a bit of juice it returns to 1500-1600rpm..

Can't complain!

Was gonna get a TPS - but will hold back on that for a few more rides..

 

[black knight]

ran it 300km today.
-24C in the morning.- cold start rumble still there
idle solid all morning except once, it fell down to 1300rpm
at a stop.
Warmed up to +2C and it did it a couple times but would only fall
to 1300rpm at road crossings. touch throttle and it would hold at
1600rpm and then i couldn't get it to drop if i tried.
So its 90% better.
Mileage is a bit better than before i set Co to -12

 

[Trailblazergt]

Thanks for all the info on the CO settings guys but....putting aside Black Knights last post i would like to know a little more about what the outside temperatures verses the CO settings you guys have set too and ride too.

Has any one had the courage to ride WOT with like -10 CO settings and also would anyone share their fuel tank range with their CO settings.

Thanks in advances guys

 

[02xtreme]

Thanks for all the info on the CO settings guys but....putting aside Black Knights last post i would like to know a little more about what the outside temperatures verses the CO settings you guys have set too and ride too.

Has any one had the courage to ride WOT with like -10 CO settings and also would anyone share their fuel tank range with their CO settings.

Thanks in advances guys

CO only controls idle to 1/8 or 1/4 throttle from my research. Mine is set at -15 CO, the gauge goes beyond -100 (I'm not sure the max?). When its warmer outside (-2 Celsius today) I find it tends to idle a bit lower around 1300 if I let it sit idling for a few minutes. When its colder it runs perfect the entire time. At -10 CO I was still getting a cold start stumble, at -12 CO it was better and at -15 CO its non-existent. Hope that helps.

 

[black knight]

o2extreme you got the cold start rumbble out of it??

i will have to drop it to -15
and see

 

[02xtreme]

o2extreme you got the cold start rumbble out of it??

i will have to drop it to -15
and see

2 successful starts so far with no stumble

 

[JROCK]

I will try dropping mine down a bit more from -10 as i still have the cold start stumble. Seems worse when warmer out. As stated this adjustment is like changing the pilot jet on a carb model. Has no effect on WOT operation.

 

[Trailblazergt]

I will try dropping mine down a bit more from -10 as i still have the cold start stumble. Seems worse when warmer out. As stated this adjustment is like changing the pilot jet on a carb model. Has no effect on WOT operation.

So in an effect no danger of leaning out regardless of temperature and WOT, this adjustment is strictly for start up and idling?

I read guys were getting better fuel range with this adjustment, wondering how this adjustment would work that way if it was for startup and idle.

Sorry for novice questions guys but this is a new area on my Apex to learn about.

 

[JROCK]

I see no harm done as this adjustment only affects the low speed adjustment like in carbs 1/8 -1/4 throttle. Fuel mileage will go up slightly by leaning out if you stay in this range of the throttle. With all the torque this sled has you can stay in this range for bush running or riding with the wife lol. Anything above that and it will be the same.