whats best pinion 12 or 13

[Ross Northcott]

Whats the best pinion to use on a helijive with a target headspeed of 2300rpm?
1) 12t gives a headspeed of 2300 at 87%
2) 13t gives a headspeed of 2300 at 67%

And the reason why?

[GIXERMAN]

i would say 12t because motor will be more torquey and battery more duration, but 67 sounds better on the number for gov imo

[vinny155]

it depends on wheather or not you have calibrated your tx to the jive if not the 13 looks good as at 67% you are running around 83% of motor pwn,reccomended %

[Ross Northcott]

it depends on wheather or not you have calibrated your tx to the jive if not the 13 looks good as at 67% you are running around 83% of motor pwn,reccomended %

Vinny you dont calibrate the helijive mate if using the bailout feature.

[vinny155]

cheers ross,here is an explanation i stumbled accross on helifreak

I recently learned how to calculate the correct values for governing within the Jive and wanted to share. This is not my findings this is after talking with the owner of Kontronik (very smart man).

Basically you are shooting for PWMout of ~80% this gives the ESC enough overhead to manage rpm throughout the entire length of the flight. in order to calculate this you use the following formula

PWM out = 50% + (Tx% / 2)

so for a value of 65% flat curve in the TX this gives you:

50% + (65% / 2) = 82.5% PWM

This is the suggested max value.

60% is also a good value giving you the following:

50% + (60% / 2) = 80% PWM

Now this does differ from the Kosmik and Koby. They take the PWMout directly. When you put 80% in the TX thats equal to 80% PWM on both the Kosmik and Koby. This is explained in the Kosmik manual and it is a bit easier with that one to tune the PWM to your flying style by looking at the logs and observing the times at which you hit 100% PWM.

So basically keep your flat line throttle curves between 60% and 65% on the transmitter for optimal performance. And remember NEVER attempt to reduce or "calibrate" your end points in the transmitter.


Definitions:
PWM (Pulse Width Modulation) is basically the average time that the esc is in full current output mode. The higher the better here because if you are flying hard current is used to compensate for too low PWM which means excess heat. but too high is also bad because once its capped out at 100 your rpm can still drop and the esc has no ability to correct for it.

[Ross Northcott]

cheers ross,here is an explanation i stumbled accross on helifreak

I recently learned how to calculate the correct values for governing within the Jive and wanted to share. This is not my findings this is after talking with the owner of Kontronik (very smart man).

Basically you are shooting for PWMout of ~80% this gives the ESC enough overhead to manage rpm throughout the entire length of the flight. in order to calculate this you use the following formula

PWM out = 50% + (Tx% / 2)

so for a value of 65% flat curve in the TX this gives you:

50% + (65% / 2) = 82.5% PWM

This is the suggested max value.

60% is also a good value giving you the following:

50% + (60% / 2) = 80% PWM

Now this does differ from the Kosmik and Koby. They take the PWMout directly. When you put 80% in the TX thats equal to 80% PWM on both the Kosmik and Koby. This is explained in the Kosmik manual and it is a bit easier with that one to tune the PWM to your flying style by looking at the logs and observing the times at which you hit 100% PWM.

So basically keep your flat line throttle curves between 60% and 65% on the transmitter for optimal performance. And remember NEVER attempt to reduce or "calibrate" your end points in the transmitter.


Definitions:
PWM (Pulse Width Modulation) is basically the average time that the esc is in full current output mode. The higher the better here because if you are flying hard current is used to compensate for too low PWM which means excess heat. but too high is also bad because once its capped out at 100 your rpm can still drop and the esc has no ability to correct for it.

So if i'm reading it correctly the 13t would be more optimum ?

[vinny155]

yes defiantly if you are on the freak,go to kontronic forum and search" best percentage" ,13 tooth is the way to go

[Jamin_00]

It is perfect to be at 67% on the Helijive (Mode 4 and 5) and will leave the gov room to work. If you go above this recommendation of 65-70% TC, the PWM moves up and leaves less room for the Gov to work effectively = more bogging and over speeding.