I am not sure which device you are targeting , Here is the screen shot example for Cyclone V. In IP megawizard you can change the core output clock to 1,2 , 4.
Thanks for the reply. I think it is my fault. Everthing in the parameter settings above talks about the input and core clock. Nothing on the output clock. So I assumed te divide ratio was based on the input clock!
I am using Cyclone 10 parts with a serial link of seven bits per. So I need a divide by seven which was one of my options on the screen above.
Now runs fine.