2007 Mini Cooper - Driver window slow opening

[amzsagoo]

Hi All,

i have a 2007 Mini Cooper and the driver window is very slow to go up and down.
i changed the motor a few weeks back but i DONT believe its because of the motor.

Sometimes it works and sometimes i doesn't (always slow).

i took the weather strip off the outside of the window and tested but still slow.

any ideas?

regards
amz