Gear ratio

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btheli
Posts: 86
Joined: Fri 26. Sep 2014 20:08:26

I'm giving 1.3.2 another try on my Gaui X3. The main gear has 131T and I have a 10T pinion, so the gear ratio is 13.1. The software will only go as high as 12.7. What should I do?
ZeXx86
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The best way is to use 11T pinion, because gear ratio is very high and power system can be inefficient.
There is also way to set sensor divider differently, but I have to know what is your value.
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btheli
Posts: 86
Joined: Fri 26. Sep 2014 20:08:26

10p motor so sensor divider is 5.

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ZeXx86
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You can set
Sensor divider to 6
Gear Ratio to 10,9

Then the result should be same as with 5 and 13.1.
The values are used only for RPM calculation, both are multiplied.
6 * 10,9 = 65,4
5 * 13,1 = 65,5

The difference could be max. 4 RPM which is under resolution of the sensor.
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elfew
Posts: 226
Joined: Sun 25. Aug 2013 9:14:16

Ok, anyway this is a little bit tricky way. It should be supported by spirit itself without this recalculation
DX9 - Chase 360 - Spirit
ZeXx86
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Gear Ratio higher than 12 is very atypic and shouldn't be used from our point of view.
Same limit is also in other FBL systems, for example V-Bar.

We will check what is the best solution for this issue.
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btheli
Posts: 86
Joined: Fri 26. Sep 2014 20:08:26

Thanks. I'm in this situation because I picked up a fairly high kv motor (1860) for my Gaui X3, which is well-suited for running higher head speeds. The heli is very snappy indeed, but my flight times also dropped significantly. I may replace the motor with a lower kv, but I thought I would first see how it ran with a 10T pinion instead of the 11T. Thanks again for your help.
elfew
Posts: 226
Joined: Sun 25. Aug 2013 9:14:16

Zexx, I agree of course, but the way you wrote seems to me really "hacky". I just recommend to leave this on users choise...it is their fly style and it is only up to them which gear ratio use
DX9 - Chase 360 - Spirit
elfew
Posts: 226
Joined: Sun 25. Aug 2013 9:14:16

Anyway I understand that this limit can avoid problems with spirit governor in some circumstances.

I like the way in CC esc. There is a recommended setting displayed for the set gear ratio. Maybe something like icon with different colors in spirit setting tab next to the rpm would be nice.

Red color - gov out of range
Yellow - at the edge or something like this
Green - within range, gov should work correctly
DX9 - Chase 360 - Spirit
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