I just bought a set of Schwalbe Pro One tubeless 25c tires and found that they only left me with about 1 mm of clearance on my fork. They are a little higher volume than expected, and don't quite comfortably fit on my 2014 Orca, which is on the tighter side re: tire clearnace. Bicyclerollingresistance.com measures their width at 27 mm and height at 23 mm. These tires are 2018 version. They have about 70 miles on them. Selling them cheap to get them on a bike that works better for them.
Let me know!