Martin,
I asked Brian Marsh this question in 2006 after I bought an SD70ACe from the first run. He advised using 45” or 49.5” radius curves for the Overland O-Scale SD70ACe. He also said that the 40.5” radius might work if the speeds were low & the track joints were very smooth. But this was when I first got into O-Scale & was only aware of fixed radius curves, before I became aware of Atlas-O flex-track. So 54” seems doable.
These are just my opinion,
Thanks,
Naveen Rajan
Mike, thanks for that great explanation/illustration. I also try to enjoy my MTH -2's for what they are.
Can you tell us what the min radius for those OMI units is? (Specifically I was wondering if they will go around a 54" radius)