Headlight problem ( sleepy eye O o )

[mc mate]

I searched the forum for this and i found a topic on this problem but no solving, so here i go :

today mounted my Pivot ( i got it for 30 $ ) and one of the motors i think it is slower and when the headlights go down the slowest one remains upper, how can i change this problem ? can i put a rezistence on the one that goes fast so i can slow it down or do i have to change the motors ? if i do that how do i now that the one that i will get is not slower or not matching the other ?

If u look closely u will see that the passenger side one goes faster

http://www.youtube.com/watch?v=wW2d3fp10Fk