The TV series "Long Way Round" features some of the bikes made at the OCC workshop. The names for the bikes can be found on their website (I'm looking through it now, but what should we use for the make name? I think OCC buys in the engines, gearboxs etc. from Harley and some companies and builds the bodies of the choppers themselves.

If OCC is well-known we could use that as name?
Or we could list them as Harley Davidson? Anyway at least half of these on the site are heavily modified.

OCC is VERY WELL known in the US

So should it be "OCC" or "Orange County Choppers"?

"OCC" sounds more like a make than the full name, but I do not know

The name of the manufacturer is Orange County Choppers. See their logo at: http://www.orangecountychoppers.com/