Possible rotorhead problem?

[kalleb]

So, I have a 4g3 that I have not flown much.

I upgraded with BL tail, but it does not hold the tail.

I just changed the BL motor, and still, I cannot trim it to hold the tail - i must compensate all the time.

I noticed that my rotorhead is very "loose".
http://youtu.be/quSG-mQAXic

1. can this effect the tail?
2. can I somehow tighten the head - or must I replace it?

Cheers.