Mtn-Track
Extreme
OK, so I thought this was the best place to ask this with all the tuning going on here.
I have a (currently) stock, non-bosted '07 Apex Mtn that's running rich and I want to lean it out.
First: Does the '07 have the adjustable fuel profile in the system diagnostics?
Second: If so, what would be the stock setting, then a best-guess setting for running from 8000ft elevation on up?
I want to get it running better first, then shed weight, THEN go for the boost, all in due time......
I have a (currently) stock, non-bosted '07 Apex Mtn that's running rich and I want to lean it out.
First: Does the '07 have the adjustable fuel profile in the system diagnostics?
Second: If so, what would be the stock setting, then a best-guess setting for running from 8000ft elevation on up?
I want to get it running better first, then shed weight, THEN go for the boost, all in due time......
TBird
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All Apex, 06 and forward, have the ability to adjust idle setting thru the diagnostic mode.
Think of the setting as changing pilot jet in an carburator, so all adjustment is when engine idle and very little effect up to 1/8 throttle.
To be able to adjust fuel everywhere a piggyback EFI is needed, such as PowerCommander, RapidBike, a.s.o.
Think of the setting as changing pilot jet in an carburator, so all adjustment is when engine idle and very little effect up to 1/8 throttle.
To be able to adjust fuel everywhere a piggyback EFI is needed, such as PowerCommander, RapidBike, a.s.o.
Mtn-Track
Extreme
Thanks Tbird.
It definatley needs to be leaned out at idle, but I don't want to mess with an EFI controller before I get into boosting it. Is there a setting curve listed anywhere or do you just keep adjusting it until you find the sweet spot at idle?
It definatley needs to be leaned out at idle, but I don't want to mess with an EFI controller before I get into boosting it. Is there a setting curve listed anywhere or do you just keep adjusting it until you find the sweet spot at idle?
TBird
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Exactly, start with maybe -5, then -10, after a couple of tryes you hit the sweet spot!
Mtn-Track
Extreme
Thanks! 
kinger
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How do you know its rich?
Mtn-Track
Extreme
It's always on the ragged edge on a cold start. If you make the mistake of bumping the throttle before its had a chance to warm up for at least 15 minutes it'll immediately fowl out the plugs and quit. Every time it's done that I've had to pull the plugs to get it to re-light. 
I don't think this thing was ever been adjusted off sea level settings and it always smells rich and smokes out my trailer while it's running. The plugs are always black when I pull them, but I have yet to pull them on top of a good hill climb and probably won't anytime soon. Thus the question.
I don't think this thing was ever been adjusted off sea level settings and it always smells rich and smokes out my trailer while it's running. The plugs are always black when I pull them, but I have yet to pull them on top of a good hill climb and probably won't anytime soon. Thus the question.
mbarryracing
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I'd think that with EFI, the ECU would auto comp for altitude... or this forum would be overflowing with high altitude riders with rich fouling problems on Apex's?
I'd venture to say you have something else going Katywompus, like a sensor or fuel pressure regulator...
I'd venture to say you have something else going Katywompus, like a sensor or fuel pressure regulator...
kinger
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Correct it adjusts based on barometric pressure. I have never fouled a plug in any yamaha 4 stroke since 2004, I think you have another issue.
Mtn-Track
Extreme
That's what I'm trying to figure out.
I had a Yamai sled mechanic tell me that these things are known for running rich and this one seems to be the case. I know the EFI should (and does) compensate for altitude, but how the ECU is set-up to control it is what I'm wondering about. I'm assuming it has a pre-programed A/F curve that is led by a baro and/or stoich sensor, but I was hoping you could alter the curve for the entire RPM range and not just the lower 1/8th of the throttle with the existing system diagnostics. I want this to run better before I start any engine mods so I'm not fighting an unrelated issue.
You may have figured out that I don't have a full service manual on this thing that gets into these details...but i'm also not getting any fault codes.
I had a Yamai sled mechanic tell me that these things are known for running rich and this one seems to be the case. I know the EFI should (and does) compensate for altitude, but how the ECU is set-up to control it is what I'm wondering about. I'm assuming it has a pre-programed A/F curve that is led by a baro and/or stoich sensor, but I was hoping you could alter the curve for the entire RPM range and not just the lower 1/8th of the throttle with the existing system diagnostics. I want this to run better before I start any engine mods so I'm not fighting an unrelated issue.
You may have figured out that I don't have a full service manual on this thing that gets into these details...but i'm also not getting any fault codes.
