Speedo problem after changing chain and sprockets!

Hey guys just wondering what you all thought. I changed my sprockets and chain today. When I went for the test ride I noticed that my speedo was bouncing all of the place and would not hold a consistent speed. So I went home and took out the speed sensor from the housing and then watched it go onto the bolt holding the inner sprocket on. It just barely makes contact. I also noticed that when I spin the rear wheel that the speed sensor seem to slip some of the time. Anyone had this problem? I am trying to decide if I need to take it all back apart and get a different front sprocket or just try to add a washer so that the speed sensor makes a better contact.

 

When I did mine there was a spacer that had to go in with, if memory serves right, or the sprocket had to be facing a certain direction to work properly. You will also need a speedo healer if you don't have one already.