Granite Arrma Granite cogging

[Diem Turner]

I only see one thread.

lol...so it would appear. Don't mind me. I just work here.

YOU MERGED THE THREADS AND ARE GASLIGHTING ME, AREN'T YOU?!

I kid, I kid. Dunno what I thought I saw.

 

[Donovan]

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 Just don't like the cogging.

 

[Diem Turner]

I Just don't like the cogging.

Well, I'd say you have two options....well three really. Either you get yourself a sensored ESC/motor combo, or just get a lower KV big block that just has a metric forkton of torque. Or just get a Hobbywing Max8 combo, shouldn't even need to be sensored. I watch people run those smooth as buttah all the time and they're not sensored. Maybe get a second opinion but I think that's probably your best course of action if the cogging is really that much of an issue.

 

[Donovan]

I have driven a Traxxas Rustler VXL and that didn't cogg, is that system an option? And why doesn't it cogg?

 

[Diem Turner]

I have driven a Traxxas Rustler VXL and that didn't cogg, is that system an option? And why doesn't it cogg?

I'm not familiar with the electronics of a Rustler but, generally speaking, you should be able to just transplant the system and try it out to see if it rubs your rhubarb. Why it doesn't cog whereas what you have in there now does can be a variety of reasons. Insufficient torque to get it moving fast enough and, since it's not sensored, the ESC gets confused about the position of the rotor and doesn't know which of the three phases to fire to make it rotate smoothly. All the sensor does is read the back EMF from the motor which tells it where in the rotation the rotor is relative to the stator. Knowing where the rotor is makes for smooth starts.

The Rustler doesn't have a sensored system as far as I know so that's obviously not the reason why it's not cogging. Could just be a beefier motor but this is just conjecture on my part as I know nothing about the Velineon systems. Swap it out and give it a go. Shouldn't be rocket surgery and that way you can see if it cures what ailes ya.

 

[Donovan]

I'm not familiar with the electronics of a Rustler but, generally speaking, you should be able to just transplant the system and try it out to see if it rubs your rhubarb. Why it doesn't cog whereas what you have in there now does can be a variety of reasons. Insufficient torque to get it moving fast enough and, since it's not sensored, the ESC gets confused about the position of the rotor and doesn't know which of the three phases to fire to make it rotate smoothly. All the sensor does is read the back EMF from the motor which tells it where in the rotation the rotor is relative to the stator. Knowing where the rotor is makes for smooth starts.

The Rustler doesn't have a sensored system as far as I know so that's obviously not the reason why it's not cogging. Could just be a beefier motor but this is just conjecture on my part as I know nothing about the Velineon systems. Swap it out and give it a go. Shouldn't be rocket surgery and that way you can see if it cures what ailes y

The Rustler is a friends car, I don't think he would like it if I used his electronics.
Also, i'm running the Granite on 2s. Could that be making it cogg even more?

 

[Diem Turner]

The Rustler is a friends car, I don't think he would like it if I used his electronics.
Also, i'm running the Granite on 2s. Could that be making it cogg even more?

Oh...well yes. Drop and 3S battery in there and I'd bet dollars to pesos that you'll see a big difference. Yeah...those are the kind of details that change the complexion of an issue from top to bottom. Forget everything we've talked about. At least until you've tried a 3S battery. Let us know how it goes

 

[Donovan]

I will have to buy a 3s battery. It may take a while but I will keep you posted. Thanks!

 

[slick2500]

Well, I'd say you have two options....well three really. Either you get yourself a sensored ESC/motor combo, or just get a lower KV big block that just has a metric forkton of torque. Or just get a Hobbywing Max8 combo, shouldn't even need to be sensored. I watch people run those smooth as buttah all the time and they're not sensored. Maybe get a second opinion but I think that's probably your best course of action if the cogging is really that much of an issue.

The Arrma BLX185 with a Leopard Hobby 4282 1680kv motor is butter smooth on 4s.

 

[Xpress..]

The Traxxas system will cog with the right components. I think they generally don't cog because of the finer gearing and higher pole count in the motors.

 

[slick2500]

The Traxxas system will cog with the right components. I think they generally don't cog because of the finer gearing and higher pole count in the motors.

Aren't both the Spektrum and Velinion both 4 pole motors? I'm almost positive that they are geared differently though.

@Donovan i would pull the power module and check the motor bearings there is a high probability that they are full of dirt and that would definitely cause a problem.

 

[Donovan]

I don't think it's the motor bearings. I have not driven the Granite in water or mud.

 

[slick2500]

I don't think it's the motor bearings. I have not driven the Granite in water or mud.

Doesn't matter dirt gets trapped in the motor module and wreaks havok on the bearings in the motor. The finer the dirt the more compounded the problem becomes.

There are a few things that you can do to try to help, cut a slot in the chassis under the spur gear or put a washer and oring under the pinion gear but ensure that they move freely and do not restrict the motor.

-edit- I never get my rc cars wet or drive them in the mud or water. This is what I pull out of my 3s motors all the time.

 

[Donovan]

If the 3s battery does not solve the problem I think I will try a 3670 3050kv motor. It seems to have worked for Rich Duperbash.

Doesn't matter dirt gets trapped in the motor module and wreaks havok on the bearings in the motor. The finer the dirt the more compounded the problem becomes.

There are a few things that you can do to try to help, cut a slot in the chassis under the spur gear or put a washer and oring under the pinion gear but ensure that they move freely and do not restrict the motor.

-edit- I never get my rc cars wet or drive them in the mud or water. This is what I pull out of my 3s motors all the time.

View attachment 266142

View attachment 266143

Wow! Did not know that, I will be cleaning my bearings.