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It saves power. If the H7 lamp has greater persistence (is slow) then feeding it the slowest possible modulated signal (lowest on in the duty cycle) without having it dim would save you some amount of power, perhaps a lot. It all comes down to duty cycle. Why it would be important to save that power is probably a different discussion.
Thank you, didn’t know that. Is that a technology widespread in the automotive world? I fully understand how that would influence generator size, wire gage and so forth.
 

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Thank you, didn’t know that. Is that a technology widespread in the automotive world? I fully understand how that would influence generator size, wire gage and so forth.
I am not sure that its widespread in automotive but as we move forward with a focus on overall efficiency of the car as a system I would guess that we will see it far more often. Power for accessories is energy coming from somewhere, and as we tweak the normal ICE for maximum efficiency we have to start looking at the peripherals (AC/Generator/water pump/etc) to find ways to recover energy.

Yamaha is doing some interesting work here with 6 stroke engines and driveline-driven superchargers. Interesting if you care about horsepower anyhow :)
 

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Took off the Tupperware and measured for you, of course I picked the wrong side so all of it came off :frown:. Its straight DC. Used the bikes ground as reference I get 600mv when the fan is off and 14.2v when the fan is on. I tried a bunch of things to make the bike 'get hot' but the fan is running at a fixed speed and voltage all the time.

First pic is the fan turning on (probably a byproduct of the relay or something, kind of ugly…_), the second one is the fan completely on.. The third pic for reference is the fan in my computer running on a PWM controlled signal

so, wire away..
Excellent, thank you. I owe you a beverage or two of your choice should we ever meet face-to-face.

I will now proceed with my winter project once the ice cakes the road between here and the highway. Gonna need to make sure we don't get the flashing triangle during the little 11-day ride we have planned at the end of June next year. No idea where we are going during the ride and won't know until the night before we leave. :grin:
 

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Given the recently revealed information I now have the answers to my three questions and a winter project ahead of me.

1. Is the fan actually 12VDC or is it 100Hz square wave like the high beams?
It is DC.

̶2̶.̶ ̶I̶f̶ ̶i̶t̶ ̶i̶s̶ ̶1̶0̶0̶H̶z̶,̶ ̶w̶h̶a̶t̶ ̶w̶i̶l̶l̶ ̶h̶a̶p̶p̶e̶n̶ ̶t̶o̶ ̶t̶h̶e̶ ̶c̶o̶m̶p̶u̶t̶e̶r̶ ̶w̶h̶e̶n̶ ̶I̶ ̶p̶u̶m̶p̶ ̶i̶n̶ ̶1̶2̶V̶D̶C̶ ̶f̶r̶o̶m̶ ̶t̶h̶e̶ ̶b̶a̶c̶k̶ ̶s̶i̶d̶e̶?̶
RETRACTED

3. If it is actually 12VDC, what will the CANBUS do when it finds it cannot turn off the fan when it wants?
Doesn't matter anymore. I will prevent 'feedback' to the CANBUS and probable interference by simply installing a diode in the line to prevent my auxiliary power from going anywhere except directly to the fan.
 

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It saves power. If the H7 lamp has greater persistence (is slow) then feeding it the slowest possible modulated signal (lowest on in the duty cycle) without having it dim would save you some amount of power, perhaps a lot. It all comes down to duty cycle. Why it would be important to save that power is probably a different discussion.
I could be wrong, but I doubt its purpose is to save power. More likely, it is to regulate the brightness/temperature as the voltage and ambient conditions (temperatures) vary by varying the duty cycle.
 

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I could be wrong, but I doubt its purpose is to save power. More likely, it is to regulate the brightness/temperature as the voltage and ambient conditions (temperatures) vary by varying the duty cycle.
Certainly if you are varying the brightness that is what you would do, my take away from the reference post is that it sits at a rock solid 100hz.
 

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Saving power in the context of a k1600 makes perfect sense. The two high beams add 110 W nominal to the power draw which is something like 20% of the generator capacity. The bulbs do not create inductive or capacitative load and are ideal targets for such power saving strategy.
In one of m earlier post I was wondering about the heat regulation of the seat and grip heater. They seem to receive power based on what is left for them. Can anybody look at the power control strategy? Maybe there is a similar approach as to the high beams.
This is getting interesting.

Thanks guys
 

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Certainly if you are varying the brightness that is what you would do, my take away from the reference post is that it sits at a rock solid 100hz.
I wasn't thinking it was to vary the brightness itself but to regulate it relative to the voltage. If not, as voltage shifts around, the brightness would too. You can do that with a solid 100Hz signal by changing the duty cycle, not the frequency.
 

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I wasn't thinking it was to vary the brightness itself but to regulate it relative to the voltage. If not, as voltage shifts around, the brightness would too. You can do that with a solid 100Hz signal by changing the duty cycle, not the frequency.
Agreed its possible although the bike probably isn't going to be happy if the voltage drops significantly enough to cause problems, the bike-puter seems to be sensitive to those kinds of issues. Wouldn't surprise me either way though.
 
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