Mid -late 80's funny bike with the wrong fork - could have come with a front wheel anywhere from 24" to 700c, and without the front fork I'm not sure how easy it is to determine. At this point these style frames are not really in high demand.

The bend in the down tube doesn't really look quite right, either.

I notice that this one has track ends - I don't know if any of the track versions had different sized wheels. That may mean a standard 700c fork and wheel would be appropriate. EDIT: I did find a picture of a track funny bike with multi-size wheels - but not a single one, road or track, with a bent down tube.