Color Registration problems in my Komori L 428 year 2000

Hi
I have just installed a Komori L 428 and seem to have an issue when I print lower GSM papers like 70 and 90 .
The color registration does not seem to be a problem while printing heavier stocks .
The color registers on one side ( operators side ) while the Colors don’t seem to register from the middle of the sheet to (Motor side )
Can some one here let me know what could be the problem .
Will appreciate any help
Thanks

 

Please clean the gripper tips and pads and reset the grippers.

 

I have uploaded the left and right registration marks , although the right side of the paper registers almost perfectly the opposite side is clearly out of register .
The gripper yo tail does not have much of a problem it is the expansion of unit 1 ( black) to the sides that is a problem .
Can any one help ?

 

Wrong grain paper? Grain should run across the sheet from side to side not front to back.

 

one option would be getting through impression your paper stock before print