If any of you can enlighten me as too how this Secondary throttle valve actuator works I sure would appreciate it. It is a 4 wire unit and is not spring loaded so its does not return to a closed position with the key off. I thought from what I read that this could be PWM, frequency or Duty Cycle controlled but it does not seem to be any of these unless I have the capture wrong. Thanks in advance. I have plotted the RPM and the Secondary TPS opening as well for reference.

As as a side note I had a problem with this bike not running over 9,000 rpm. I determined that this secondary valve was not opening fully at that rpm. Turned out that I had too much AC Ripple (like a volt) from a bad Reg/Rec.

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Have you ever heard the term stepper motor?

Spence, yes I have. Why the secondary tps then? I thought most steppers ran in open loop?

James, struggling a little here, seems wrong, but maybe not.  I did for some thought put red and blue channel with filter on in the Giff.

I think your TPS and Crank sensor (RPM) are switched. That said TPS has RPM raising while it is turning off and trying to correlate fueling in Red and Blue with that thought. Will look at it some more and maybe somebody with larger brain than I will give us some input.

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Hey, a late Merry Christmas and seasons greetings to you Larry and everyone else on here. Been gone on holidays so I'm a little behind  my time as they say. The hookup is right, keep in mind that this is a secondary butterfly valve that is before the primary throttle body valve. It is there to alter the intake velocity. You can see that it actually closes some as the engine accelerates. I'm just not sure if it is confirmed with a stepper motor or servo. I have a similar setup on another bike that it looks like I might get to pull apart and find out for sure. Let you know what I find.  :)

Okay
James H wrote on Jan 2^nd, 2018 at 5:35pm:

a secondary butterfly valve that is before the primary throttle body valve. It is there to alter the intake velocity.

James,Okay, makes sense. I think the same thought process in the car world is called an intake runner. The thought in cars is it either lengthens or shortens the intake length, (that is the thought)  thus adapting to RPM and such making for more torque in some places, and then less in others making better use @ high RPMs, just depending, above my pay grade.

Again with out looking @ a unit with no problems, we don't really know what a good working one works like, and that part of this system you have captured might be good. That is why over time especially for you in the bike trade need to capture any chance you get from a good working bike in your bay for future REF, as you are a little handicapped as the bike industry IMO does not have people compiling known good wave forms, shoot, my guess is you are one of the very few even using this tool, could be wrong, but doubt it?

As stated maybe somebody else will chime in as bikes an animal all of their own but most of it will transpose from the car world.

StitchB