Hi Paul,
Was out of the office in London Thursday and Friday of last week and Brom don't do phones, so I apologise about that.
I checked all of the bolts in the bells before putting them on as the kit had been stood for well over a year and all was well. I guarentee there is movement on both disks, but the one may be really tight or fouling on the pads or something. As Martin says, let us know the gap and we'll go from there.
Give me a call when you get a chance, I have PM'd you my mobile number.
Sean..