Steady throttle hand?

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UselessPickles

Making Grand Canyon replicas from air boxes...
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While reviewing some data logs from my Motty AFR Tuner, I found it quite interesting just how much the throttle position bounces around when I think I'm holding it fairly steady:

datalog_steady_speed.jpg


The lines on the chart from top to bottom: speed, RPMs, throttle position, then actual AFR and target AFR at the bottom. The main scale on the left is for throttle position. A time span of 1 minute is shown.

For comparison, check out how smooth the throttle is when cruise control is engaged:

datalog_cruise.jpg


 
Every time little vibration of the bar moves the grip relative to the bike. You're probably holding the grip, but the bar moves inside it as the bike bounces, which moves the throttle.

That's my guess, anyway.

 
Every time little vibration of the bar moves the grip relative to the bike. You're probably holding the grip, but the bar moves inside it as the bike bounces, which moves the throttle.
That's my guess, anyway.
That's pretty much what I was thinking. Any little bump in the road, gust of wind, shift of body weight, slight steering input to the handlebars, hiccup, etc. could easily bounce the throttle hand around slightly. It doesn't take much movement to change throttle position by 5%. That's only 4.5 degrees of rotation of the grip (there's only a total of 90 degrees of motion from zero to full throttle).

 
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