Is this normal?

[Phil5556]

The juddering / notchy-ness when pushing car along like in this video? 

https://drive.google.com/file/d/1WzQBcvNoH6qG71QwR-j4dkEt_v5G9B-E/view?usp=sharing

Push it a bit quicker and it goes away but it's there initially. Doesn't do it with the motor out so it's definitely the motor or meshing of the gears. Drives normally with no apparent issue.

I presume it's just the effort needed to push the motor around and overcome the strength of the magnets?

Cheers

[Wooders28]

24 minutes ago, Phil5556 said:

The juddering / notchy-ness when pushing car along like in this video? 

https://drive.google.com/file/d/1WzQBcvNoH6qG71QwR-j4dkEt_v5G9B-E/view?usp=sharing

Push it a bit quicker and it goes away but it's there initially. Doesn't do it with the motor out so it's definitely the motor or meshing of the gears. Drives normally with no apparent issue.

I presume it's just the effort needed to push the motor around and overcome the strength of the magnets?

Cheers

Your not the first person to ask, but yes, the magnets.

Here's 2 of mine :-

 

[Phil5556]

Cheers thought it was probably OK, it's much worse than my other car.

Is it worse on brushless?

[iluvmud]

4 minutes ago, Phil5556 said:

Cheers thought it was probably OK, it's much worse than my other car.

Is it worse on brushless?

not necessarily, depends on magnet strength

[Phil5556]

Cheers I'll stop worrying and go to bed

[topforcein]

i thought i was the only one with that problem.

i run a speed passion set up also in my stadium blitzer and the noise goes away when in use but the same as yours is their when pushed.

my lhs calls it cogging 

[TurnipJF]

It sure ain't cogging! Cogging affects sensorless motors under power, usually when accelerating from a standstill. Sensored motors are pretty much immune unless malfunctioning, and neither type would cog without power!

 

The phenomenon noted by the OP is caused by the magnets of the rotor "clinging" to the stationary parts of the motor as it is rotated without power. The two primary factors affecting it are the strength of the magnets and the distribution of ferrous metal within the can.

 

As previously stated by other respondents, it is not a fault and is perfectly normal. 

[nowinaminute]

This is called cogging too, the term has been been associated with sensorless brushless motors in recent years but the term originally meant the way the rotor jumps between magnets. The two issues are seperate phenomenon although there's some overlap for example a sensorless brushless motor that has strong magnetic cogging will suffer more from "brushless cogging" 

[topforcein]

in all fairness my stadium blitzer makes more noise than the ones in the videos i brought both the truck and motor/esc setupp from my lhs so i decieded to take it back there and the chap i always go to in there plus the owner do know there stuff. 

but as i have said the description of the noise is from them and not me an any way.

he did explain to me at the time but its been a coupe of years ago and i can't remember that know.