mbarryracing
TY 4 Stroke God
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2015 SR Viper RTX-DX
1996 Vmax 600XT
Not sure yet, depends on if there is enough snow and if I do it will only be to help and watch, not race...fxnytroxtx said:
There is a local snow drag race in Arcade NY on that same Sunday the 12th that I'd really like to go to and try out the Apex. Depending on if they have snow, too...
mbarryracing
TY 4 Stroke God
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2015 SR Viper RTX-DX
1996 Vmax 600XT
OK guys, after a few messages and an awesome phone conversation, it's clear that we need to clarify a few things to prevent any further confusion since it's apparent we have two different discussions going at the same time here.
The acceleration burble / hesitation at 6000 RPM (after an on-off then back-on again throttle condition, etc) is a different concern then the deceleration stumble and stall concern. They appear to be unrelated to each other, so just an FYI so you guys aren't chasing your tail... treat them separately for now.
First off, after talking with some of my very good yamaha tech savy friends, it's apparent now that I was correct when I had commented previously that I thought I experienced that on a stocker... because the slight hesitation / burble you guys are experiencing during the initial acceleration when you wack the throttle open is an inherent trait of a stock Nytro that you won't get rid of as long as you have the stock ECU. This burble is a result of Yamaha's built in EBRS "Engine Braking Reduction System" action on a Nytro and not the turbo system or a controller setting.
Per Yamaha FX Nytro Technical documents explaining EBRS... to reduce the engine braking effect during deceleration, the idle Speed Control valve (throttle plate by-pass) opens when the throttle is released (starts when gets below a given position). This allows additional air to pass into the intake and reduces the negative pressure in the intake tract (vacuum resistance) and results in the rider having more "coast" feel (like a 2-stroke) when the throttle is chopped closed.
Well guess what guys, that subsequent introduction of additional air causes a momentary lean condition that you can't tune out, causing that burble / hesitation. You have this on the stock machine but it just becomes more pronounced with modifications that increase air flow characteristics such as add-on exhaust, and turbos... so your probably going to have to live with this phenomenon with any Nytro.
Second, that stumble and stall that some are experiencing when you chop the throttle closed from WOT is still related to having the fueling too rich, separate from a burble at 6000...
The acceleration burble / hesitation at 6000 RPM (after an on-off then back-on again throttle condition, etc) is a different concern then the deceleration stumble and stall concern. They appear to be unrelated to each other, so just an FYI so you guys aren't chasing your tail... treat them separately for now.
First off, after talking with some of my very good yamaha tech savy friends, it's apparent now that I was correct when I had commented previously that I thought I experienced that on a stocker... because the slight hesitation / burble you guys are experiencing during the initial acceleration when you wack the throttle open is an inherent trait of a stock Nytro that you won't get rid of as long as you have the stock ECU. This burble is a result of Yamaha's built in EBRS "Engine Braking Reduction System" action on a Nytro and not the turbo system or a controller setting.
Per Yamaha FX Nytro Technical documents explaining EBRS... to reduce the engine braking effect during deceleration, the idle Speed Control valve (throttle plate by-pass) opens when the throttle is released (starts when gets below a given position). This allows additional air to pass into the intake and reduces the negative pressure in the intake tract (vacuum resistance) and results in the rider having more "coast" feel (like a 2-stroke) when the throttle is chopped closed.
Well guess what guys, that subsequent introduction of additional air causes a momentary lean condition that you can't tune out, causing that burble / hesitation. You have this on the stock machine but it just becomes more pronounced with modifications that increase air flow characteristics such as add-on exhaust, and turbos... so your probably going to have to live with this phenomenon with any Nytro.
Second, that stumble and stall that some are experiencing when you chop the throttle closed from WOT is still related to having the fueling too rich, separate from a burble at 6000...
raised the red blue and red orange 1 notch and seemed to help
Has anyone made some improvement , got some snow here and tried some more tuning ,have the red blue and the orange blue raised all the way, the green and the orange lowered all the way , at cruise under 7g runs 11.7 to 12.3 but when the boost comes on above 7500 af drops to the low 10s will gradually climb to 11.7 or so loads up bad if not riding hard enough , tried dropping the red some but haven't went far. Thought I may be wrong and need to change green blue Would like to get this set better and then may add boost controller to bump to 6 or 7
mbarryracing
TY 4 Stroke God
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1996 Vmax 600XT
What is your red setting at? Maybe too high...
Green -idle (pilot jet)
Orange -mid (needle jet)
Red-wot (main jet)
Blue-green - boost fuel (fuel added for boost amount)
Orange-blue - accelerator pump timing (the lower the number the SOONER it adds fuel) Opposite of what you'd think. It adjusts how much fuel when you stab it, if it pops lean when you stab it increase this, if it stumbles rich decrease this.
Red-blue - Full throttle switch point (RPM point when WOT fuel (red) engages) again, lower number is a lowe RPM when it comes on so just like above it...
On my Apex I use to run
green - 0.5 (fast blink, no fuel added)
orange - 5.5 (5&6)
Red - 5
green-blue - 3.5 (3&4)
Orange-blue - 2.5 (2&3)
Red - blue - 2.5
Green -idle (pilot jet)
Orange -mid (needle jet)
Red-wot (main jet)
Blue-green - boost fuel (fuel added for boost amount)
Orange-blue - accelerator pump timing (the lower the number the SOONER it adds fuel) Opposite of what you'd think. It adjusts how much fuel when you stab it, if it pops lean when you stab it increase this, if it stumbles rich decrease this.
Red-blue - Full throttle switch point (RPM point when WOT fuel (red) engages) again, lower number is a lowe RPM when it comes on so just like above it...
On my Apex I use to run
green - 0.5 (fast blink, no fuel added)
orange - 5.5 (5&6)
Red - 5
green-blue - 3.5 (3&4)
Orange-blue - 2.5 (2&3)
Red - blue - 2.5
my red is on 5 or middle and the green blue is maxed out. if I pull boost fuel,green blue but add to the red does it have a cumulitive effect and have the same fuel at max throttle full rpm. I raised the red blue to try to delay this spot and move it higher but no real change. It just gets to much fuel when the boost comes on at less than full throttle 1 psi to or so.
mbarryracing
TY 4 Stroke God
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2015 SR Viper RTX-DX
1996 Vmax 600XT
I know exactly what your experiencing, at first I had to fine tune it out too.
It's a transition point between fuel curves that is momentarily flogging the motor with too much fuel. Apparently the FPP program starts to add boost fuel at around 2 psi of boost.
Keep testing with maybe lowering the blue green boost fuel so you can get that transition point moved to where it isn't pronounced like that. Then if you have to, max out the red main and play with the timing with maybe making it come in earlier to compensate if WOT afr's become leaner.
It's a transition point between fuel curves that is momentarily flogging the motor with too much fuel. Apparently the FPP program starts to add boost fuel at around 2 psi of boost.
Keep testing with maybe lowering the blue green boost fuel so you can get that transition point moved to where it isn't pronounced like that. Then if you have to, max out the red main and play with the timing with maybe making it come in earlier to compensate if WOT afr's become leaner.
redrider18
Extreme
I had the same problem last year and played around with the fuel controller settings a bit. Didn't get it perfect but better. We didn't have much snow.
This year I added an inline fuel pump and 1:1 regulator to mine and have to make some adjustments. Thank you for the info mbarry.
This year I added an inline fuel pump and 1:1 regulator to mine and have to make some adjustments. Thank you for the info mbarry.
Im currently running these settings on my stage 2 kit from fpp
Green:1
Orange:1
Red:1
Green blue:1
Orange blue:4.5
Red blue:4.5
WOT a/f at 11.7
Im still a tad rich at 3psi, anywhere from 3-12psi a/f is good
Still adj for idle and cruise speeds 20mph and slower as those are a touch on the lean side with current settings
Green:1
Orange:1
Red:1
Green blue:1
Orange blue:4.5
Red blue:4.5
WOT a/f at 11.7
Im still a tad rich at 3psi, anywhere from 3-12psi a/f is good
Still adj for idle and cruise speeds 20mph and slower as those are a touch on the lean side with current settings
