Tile worlid position and tilePosition

[gotenxds]

Hello, I'm playing with the tileSprite class
 

 

I'm trying to achieve an effect where I move a tilesprite to the beginig of the screen (x=0) and then stop moving it and start moving its tilePosition.

It works fine but for some reason the speed is different.

If if move the tile itself 5 pixels it moves slower then when I change the tilePosition 5 pixels 

Why is that, is there a way to calculate the correct difference ?

 

Edit - for some reason it looks like dividing by 2 it the correct ratio, but it might be just for the specific case I'm using it in, I'd love an input if anyone has any idea.