Bigger chain ring on 2x
 

On my fx3 , I notice when I’m in the bigger ring (46/30), my drive train is not as smooth. I can hear more sound in the back derailer it’s not rubbing ,just more sound and my pedal strokes are not as smooth.
in the smaller one it rides way smoother,like butter, the shifting is about the same when moving up or down in the rear cogs.

is this true of all bikes and no matter what components you have ?

the fx3 has Acera, would it be same if I had deore, or Shimano 105 , tiagra...etc

The chain line changes when moving to the big ring, but that's a really minor thing.

The chain tension does change significantly.

The B-tension screw might need adjusting, or the chain could be too short.

https://www.parktool.com/blog/repair...eur-adjustment

so if it is in the big ring is it expected to be a little less smooth than when in the small ring ?
I don’t have any other trouble shifting is fine , just less smooth

No, the drivetrain should be equally quiet in all gears. If you are experiencing roughness in certain gears, something is wrong.

Maybe you are pushing harder and there is more tension on the top part of the chain that is pulling the rear cog, and so there is a bit more noise during the power part of the pedal stroke? If the chain is not well lubed maybe there is a bit more friction and noise during the pedal stroke?

Otto

so the bike was bought in 2020 October and just got done the free yearly tune up directly from trek that you get in the first year