I thought it was 1". The stem measure around .9" I measured the stem on my sparker, wife's Hawaii coaster, and an older coaster3. They were all the same. 22.2 sounds really close to the .9" I came up with.
The bike is the basic 26" steel cruiser. I forget if they just call it the cruiser, or cruiser 1.
I want to order the monark style springer for it.