Tekin 35t smells burnt, but not hot

[Odd-M]

Starting a new tread with my motor/esc issues.

Brand new Tekin 35t HD connected to a used FXR. Startup is rough, with a snap and not smooth as it should be. After I get it rolling I can let the trottle go back and slow down. Right before dead slow it starts with some minor stuttering.
Thougth is was radio or esc at first since the motor are new, reset setting and checked everything, tried another radio and so on. No improvement.

But after yesterdays first real test, the motor started to smell burnt after around 1 hour of use. Normally this would indicate heat, BUT strangely enough it was not hot at all. I could easily hold my fingers on the can and it was barely being warm. Temperature while driving was 5C/41F, so cooling shouldn't be an issue anyway.

Have inspected brushes and comm, seems fine to me.
Leads solderings are fine.

Any ideas?

[Cope]

Could it just be breaking in?
setting the brushes and cooking off an factory lube that got some where it should not have?

[K.O.M.]

It sounds like the high frequency switching on the Tekin FXR ESC is the thing that is fried. Check by connecting another motor that you know works, and if it is still rough, then the ESC will need to get sent back to Tekin for repair or replacement.

Check the solder joints on the PCB on the FXR; I've seen just even a small sliver of wire short out an ESC (similar to connecting the battery backwards--don't ask how I know), and it will still work sometimes depending on how long the short happened, but damage usually occurs to some degree.

[Odd-M]

It's def not break in. What's "PCB"?

[Trubble]

Printed Circuit Board