Perfect Pass off... by A LOT!

Ok, so I know there are a million perfect pass threads out there but that makes it kinda hard to search for the specific topic I am looking for. Anyway, my perfect pass is off right now by like 10mph and I cannot get it to be right. At the beginning of last season it didn't work because it rested on the trailer all winter and the protective sides got the paddle wheel stuck. It was again like that this year and I pulled them back again but it is now working but off by quite a bit. Anyone have any suggestions? It kinda sucks having to put your perfect pass at 15mph to go ride.