Engine knocking in general refers to detonation/pre-ignition.
As there's no video attached I assume you mean a knocking, mechanical noise?
What bike, type/model/year and what was the cause for the engine rebuild?
What was done to the engine during the rebuild and what oil is in it?

 

I did a engine rebuild few months ago from ktm service center but now there is a small knocking in the enging.

When i showed it to the ktm service center they're saying it's normal and notthig to worry about, But I'm fit concern about the knocking.

I have attached the video and can anyone cofirm if the knocking is normal and not any issues.

Engine knocking in general refers to detonation/pre-ignition.
As there's no video attached I assume you mean a knocking, mechanical noise?
What bike, type/model/year and what was the cause for the engine rebuild?
What was done to the engine during the rebuild and what oil is in it?

Yes actually I'm unable to attach the video my bike is duke 390 bs3 2014