I am going to get the digital calipers. Good idea vredstein. You own a tire company and post here?
It's 26.4. I took it to the place I bought the headset. It's actually a big beach cruiser store but the headset was only $8.99. The Tange Passage.
The guy that assembles bikes pounded it on there. I was a little skeptical at first. English is not his first language. I asked him to please be careful of the paint.
All is well. The build will go forward today.