Granite Arrma Granite cogging

Donovan

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I just bought an Arrma Granite 4x4 BLX V3. When I accelerate from a stand still the car coggs. the gearing is stock and I adjusted the gear mesh. I am not sure what the problem is. I am running the car on 2s lipo. Could that be the problem?
 

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At low speeds the motor will cog it is just the way sensorless brushless motors are.

Is it cogging when you gun it or when you ease into the throttle?
 

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The cogging is due to the motor being out of sync from the firing order the speed control outputs on the phases. This is completely normal operation for sensorless designs and the motor will always come back into sync once the firing order matches what the motor poles are sitting at. Every sensorless system will have this issue, some are more prevalent than others. You will notice at low RPM, the motor is relatively easy to stop turning as it is easy to force the motor out of sync with the ESC as the ESC just fires off in a predetermined interval.

Sensored systems do not have this issue as there is a physical sensor in the back of the motor that tells the ESC exactly what poles to fire to get the motor to begin turning immediately. These systems have extremely smooth operation and have immense torque at low RPM since the ESC adjust its firing order based on motor RPM.
 

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The cogging is due to the motor being out of sync from the firing order the speed control outputs on the phases. This is completely normal operation for sensorless designs and the motor will always come back into sync once the firing order matches what the motor poles are sitting at. Every sensorless system will have this issue, some are more prevalent than others. You will notice at low RPM, the motor is relatively easy to stop turning as it is easy to force the motor out of sync with the ESC as the ESC just fires off in a predetermined interval.

Sensored systems do not have this issue as there is a physical sensor in the back of the motor that tells the ESC exactly what poles to fire to get the motor to begin turning immediately. These systems have extremely smooth operation and have immense torque at low RPM since the ESC adjust its firing order based on motor RPM.
Mind blown
 

Xpress..

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One thing to take note is the stocker tx.. makes the cog appear way worse than it really is due to its ridiculous latency!! Just a thought
The SLT3 transmitter does not have this bad of latency, it's actually a decently solid radio. The cogging is purely an issue of motor to ESC relation.
 

slick2500

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Was terrible on my v2 senton.. like mind blowing 🤯
My fault @Xpress.. I'm thinking of my old stx2!! 🤔
Yeah the STX2 was a complete pile of

Poop Diarrhea GIF
 

Donovan

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At low speeds the motor will cog it is just the way sensorless brushless motors are.

Is it cogging when you gun it or when you ease into the throttle?
It coggs when I gun the throttle. It will also stutter when at low speeds.
The cogging is due to the motor being out of sync from the firing order the speed control outputs on the phases. This is completely normal operation for sensorless designs and the motor will always come back into sync once the firing order matches what the motor poles are sitting at. Every sensorless system will have this issue, some are more prevalent than others. You will notice at low RPM, the motor is relatively easy to stop turning as it is easy to force the motor out of sync with the ESC as the ESC just fires off in a predetermined interval.

Sensored systems do not have this issue as there is a physical sensor in the back of the motor that tells the ESC exactly what poles to fire to get the motor to begin turning immediately. These systems have extremely smooth operation and have immense torque at low RPM since the ESC adjust its firing order based on motor RPM.
Wow! Thanks for the super useful Information!
 

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Usually these statements "doesn't cogg" and "cheap" typically don't go together because it means you are looking for a sensored system.

What's wrong with the system you currently have?
 

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The 3100kv option:

https://www.hobbywingdirect.com/products/ezrun-max10-combo-3665sd

Why are some more prevalent than others?
That system is probably one of the less expensive systems I've seen, from a quality standpoint. OP make sure you get the 3100kv option.

Cogging is dependent on gearing, KV, voltage, vehicle weight, ESC programming, motor design, polar orientation, humidity, air temperature, solar flares, nausea, heartburn, indigestion, upset stomach, and sometimes diarrhea. 💩
 

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Usually these statements "doesn't cogg" and "cheap" typically don't go together because it means you are looking for a sensored system.

What's wrong with the system you currently have?
I'm going to go out on a limb here and say that it coggs...sight unseen. Don't ask me how I know, just....gut instinct.

You are correct though. Sensored and cheap aren't stable mates.
 
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