CVT Gearing in Datalog

Myx

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@KTuner (Or anyone for that matter)

When datalogging a long wide open throttle run, I notice the gears step up from 1-2-3-4 gears. It is said that the CVT 'has no gears'.
With this being the case, what am I seeing when I see my 'gears' change from 1-2-3-4, etc?


I just want to understand what I am looking at. Thanks!
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gtman

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You are seeing what Honda technically calls "fake gears". :cool: :drive:

I honestly don't know. Maybe those "gears" in the datalog represent different rpm ranges?
 
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disgraced.fk8

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I recall seeing something in a KTuner thread about this, and *I think* it was Ktuner themselves who replied saying it was a calculation of speed/rpm or something like that.... Can't say for certain though.
 

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Since the CVT works by changing pulley diameters to effectively change gear ratio, even though it's able to constantly change (hence CVT, continuously variable transmission), many people feel that it's unnatural to be constantly accelerating, i.e, the feeling of up/down shifts is what feels natural and people don't like when they're nonexistent as would be the case with a cvt. So what the manufacturer does is they program the cvt to 'change gears' similar to how a normal AT would, at certain rpm/speed ranges similar to those of an AT, all to 'enhance' the driving experience.
 
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Myx

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I should've been a little more specific. It shows this gear changing when I am accelerating in 'L'. Meaning you will see my rpm stay at say....6100rpm the whole time I am accelerating. However, you will still see this 1st gear, then 2nd gear, etc. I am at work now. I'll try to repost an old datalog up that I may have posted in the forums somewhere.
 


gtman

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So you're saying even though your rpms are steady at 6,100 rpm, the datalog is showing it going from "gear" 1 to 2 to 3 to 4?
 
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Simulated gears still get a designation and are calculated by the ECU with RPM vs speed. As the ratio changes, so will the "gear".
 
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Myx

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So you're saying even though your rpms are steady at 6,100 rpm, the datalog is showing it going from "gear" 1 to 2 to 3 to 4?
That is exactly what I am saying.




Simulated gears still get a designation and are calculated by the ECU with RPM vs speed. As the ratio changes, so will the "gear".
Thank you for your response. That makes sense.



On a side note, I'd like to share something with some of the other folks.
When in 'D', I noticed that the datalogs would show 1st gear 'shifting' to 2nd gear at say 25mph.
When in 'S', 1st gear would shift to 2nd gear at say 34mph.
When in 'L', 1st gear would shift to 2nd gear at say 42mph.

What I said above isn't exact as I rather show the old datalogs of this happening. The mph numbers may be different but just know that when I had the shifter in 'L', it didn't show it 'shifting' to the next gear until a higher mph than 'S'. 'S' held the same 'gear' to a higher mph than 'D'. That was one of the reasons I race in 'L', outside of it not doing the simulated shifting that we feel.

If you don't have paddle shifters, please feel free to datalog and see this for yourself. It may or may not have some benefit as far as power is concerned (holding a lower 'gear' longer into the mph). I just couldn't tell if it was real what I was seeing or something.....calculated. :)
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