Originally Posted by
jefnvk
Is there any issue with breaking them in on a trainer?
No. The saddle doesn't know or care whether the bike is moving forward or not.
Originally Posted by
jefnvk
DO they need to be broken in on the bike they are intended to be ridden on?
No. They easily accommodate position changes. I've moved several Brooks saddles from one bike to another. One that I'm currently riding was on my dad's bike in the mid-80s.