No it doesn't, it looks like a brake you'd find on a roadster, like my old 60s Sears&Roebuck, or any other 27" or old schwinn style 26". Yes and the measurement doesn't matter. That's the tire and wheel an Onyx comes with. If he measured the distance on practically any non roadbike fork, they would be the same, or very close. Any side pull that'll fit a bmx fork will fit a cranbrook, or an Onyx, the wheelsize doesn't matter, they are all pretty much the same distance. The rim is a generic rim, the height of the section is typical box rim, the tires sidewall height is typical for the tire it is. Excluding the diameter of both; you're going to see the tire is no taller then the generic white wall or whatever tire you find on 26" and 20" walmart bikes, same for the wheel. Dealing with these generic bikes ain't rocket science

This is a bmx caliper, this is what I have on the front of my LaJolla, and any other rigid fork bike that didn't have cantis or vbrakes I've built. "Long reach" is usually a misnomer, those chintzy calipers and these are most likely the same size. These are going to be a stronger brake.