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Discussion Starter #1
did it manually,one idle screw on the left and one in the middle of the motor,it was idleing at 1800 rpm now I have it down to 1250 rpm above 90 degrees when the fans kicks in, under 90 when the fan turns off it is 1350 to 1400 rpm.so my question is why do you need software to drop the idle,bike runs great.
 

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Because the problem wasn't in the air screws in the first place, the TPS value drifts with time and there in lies the problem, not in the air bleed screws.
Effectively you changed the AFR at idle with those screws.

You see, you got yourself another problem now, with no fans it runs at 1350-1400 and at 1250 with fans on. Fans off/on shouldn't affect the idle.
 

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Discussion Starter #3
Because the problem wasn't in the air screws in the first place, the TPS value drifts with time and there in lies the problem, not in the air bleed screws.
Effectively you changed the AFR at idle with those screws.

You see, you got yourself another problem now, with no fans it runs at 1350-1400 and at 1250 with fans on. Fans off/on shouldn't affect the idle.
ok, so what is the cure then,I have had the bike dyno tuned and do not want to effect that,so by dropping the idle manually what have I changed.even with the dyno done it changed rpm idle when above or below i reckon the bike heats up and changes,then the fan kicks in and changes the rpm idle,I think this is the nature of the beast.throttle response is perfect still.
 

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ok, so what is the cure then,I have had the bike dyno tuned and do not want to effect that,so by dropping the idle manually what have I changed.even with the dyno done it changed rpm idle when above or below i reckon the bike heats up and changes,then the fan kicks in and changes the rpm idle,I think this is the nature of the beast.throttle response is perfect still.

By manually adjusting the idle thoguh you potentially have altered the work you have have had done on the dyno.

Ok, lets say that your old idle of 1800rpm had the TPS at a zero position, the ECU knows this position and also see's it as 0, it is getting a voltage reading and thigns are based on that setting. the PCIII has also had it's 0% throttle position set to 0. These are the anchor points of your whole mapping process. So when you open the throttle by 5% both the ECU and PCIII know that you are at 5%, the butterflies are open by 5% and you are flowing X amount of air. The maps have been written for this and so injector timing and ignition will be suitably set.

By manually adjusting things you have now moved that Zero point to now be say -2% throttle. Now when you open the throttle by 5% the ECU is only reading you as being at 3% as is the PCIII. You are now runnign the bike on maps that are 2% lower than they should be, not so important at bigger throttle openings but crucial at low end stuff. You see at -2% the voltage reading will be lower and as such 0 throttle doesn't actually happen untill you have opened the throttle by 2%.

You need the software because this will reset the TPS position reading to make it zero and this will then set all those other maps to run at the right throttle openings. It does have similar drawbacks to manually adjusting the throttle as on MV's no two TPS's appear to be set even remotely similar but it is more precise as you are at least have closed throttle on closedpositon and 50% throttle on 50% etc etc.

this is why setting the TPS on the Microtecs is so so important. Also the first ten mapping points out of 20 usuable are for closed (2.3 degs) to 12 degs throttle. And all of them will have different fuelling and ignition requirements.

:)
 

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Discussion Starter #5
By manually adjusting the idle thoguh you potentially have altered the work you have have had done on the dyno.

Ok, lets say that your old idle of 1800rpm had the TPS at a zero position, the ECU knows this position and also see's it as 0, it is getting a voltage reading and thigns are based on that setting. the PCIII has also had it's 0% throttle position set to 0. These are the anchor points of your whole mapping process. So when you open the throttle by 5% both the ECU and PCIII know that you are at 5%, the butterflies are open by 5% and you are flowing X amount of air. The maps have been written for this and so injector timing and ignition will be suitably set.

By manually adjusting things you have now moved that Zero point to now be say -2% throttle. Now when you open the throttle by 5% the ECU is only reading you as being at 3% as is the PCIII. You are now runnign the bike on maps that are 2% lower than they should be, not so important at bigger throttle openings but crucial at low end stuff. You see at -2% the voltage reading will be lower and as such 0 throttle doesn't actually happen untill you have opened the throttle by 2%.

You need the software because this will reset the TPS position reading to make it zero and this will then set all those other maps to run at the right throttle openings. It does have similar drawbacks to manually adjusting the throttle as on MV's no two TPS's appear to be set even remotely similar but it is more precise as you are at least have closed throttle on closedpositon and 50% throttle on 50% etc etc.

this is why setting the TPS on the Microtecs is so so important. Also the first ten mapping points out of 20 usuable are for closed (2.3 degs) to 12 degs throttle. And all of them will have different fuelling and ignition requirements.

:)
ok ,point taken ,so in theory all I have to do is reset the tps setting in the pc5 and all should be fine, so it works to its original mapping.or am i way out.
 

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ok ,point taken ,so in theory all I have to do is reset the tps setting in the pc5 and all should be fine, so it works to its original mapping.or am i way out.
Really you should have reset the TPS through the software first and then mapped your PCIII.

The PCIII adjustments are made ont he fuelling that you were gettign at that set throttle opening.

As it was was 10% throttle flowed X amount of air and fuel, the bike ran rich for e.g. so at 10% throttle in the PCIII the fueling was altered by removing fuel.

Now 10% throttle is, for e.g., actually what 12% was and as such the feulling in the ECU will be different yet the PCIII is still tryingto pull the same amount out of that throttle position when it may not need it. Reset the PCIII and you are now pulling 10% fuell out of the 10% position in the ECU but your butterflies are now not open the same amount and as such not flowing the same amount of air and fuel as when the bike was originally mapped.

Does that make sense.

By moving the idle manually you have not only moved the base reference point for the TPS but also the butterflies themselves which ultimately control how much air goes into the engine which ultimately controls how much fuel is needed to match that air.


:)
 

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Discussion Starter #8
Really you should have reset the TPS through the software first and then mapped your PCIII.

The PCIII adjustments are made ont he fuelling that you were gettign at that set throttle opening.

As it was was 10% throttle flowed X amount of air and fuel, the bike ran rich for e.g. so at 10% throttle in the PCIII the fueling was altered by removing fuel.

Now 10% throttle is, for e.g., actually what 12% was and as such the feulling in the ECU will be different yet the PCIII is still tryingto pull the same amount out of that throttle position when it may not need it. Reset the PCIII and you are now pulling 10% fuell out of the 10% position in the ECU but your butterflies are now not open the same amount and as such not flowing the same amount of air and fuel as when the bike was originally mapped.

Does that make sense.

By moving the idle manually you have not only moved the base reference point for the TPS but also the butterflies themselves which ultimately control how much air goes into the engine which ultimately controls how much fuel is needed to match that air.


:)
Thanks Chris ,you are correct,makes sense.
 
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