With my 2006 Night Train which comes with a 200mm tire on it they made the belt width smaller and well i ride hard and it broke 2 times. This winter i will put a 530 O-ring chain on it. This is what i found i used the company Doherty Machine's product for the conversion. Here is the numbers.

Stock hub width from 86 - 06 : 6.375
Trans offset: 0.875
Hub with spacer to run the 0.875 offest has to be 7.2 inches.
Hub spacer has to then be 0.825
For the Rear any straight sprocket will work does not have to be dished.
530 Chain well thats up to you.

I hope all this research i did helps everyone out who has a softail who wants to run a chain.