My mistake.
I just saw on the CompARF site that the rails are designed for 100-140
Strange but I don’t recall seeing any dimensions or weight for the plane on the CARF site.
As I don’t have paved runway access and fly from grass, I would likely go with the 140, just for takeoff roll.
in your case you might want to go big with a 140, I fly at pavel runway so no need to go that big... also I spoke with Pirotti at JP and he said that a 100 is more than good... but as always there is plenty of individual circumstances when choosing the right power-plant