There are two different sizes of 16 inch wheels that are used on bikes, trikes , and bicycle trailers. Golden motors needs to specify the correct size of their wheel . There is approx 2 inch difference in wheel size. One wheel the one GM sells is the 305 ISO wheel , the greenspeed recumbent trike uses a 349 ISO wheel
The blueprint of the 16 inch wheel I was unable to read due to the contrasting colors.
GM does NOT carry the popular 16 inch wheel that is used on the greenspeed tadpole trikes, the wheel GM sells will not work on this trike due to clearance problems, it is about a 2 inch difference.
!6 inch tires that GM sells work on BOB type trailers, the front wheel of many BikeE recumbents
There are 5 different 26 inch wheels, again the need for listing the ISO/ ETRTO,
There is also a formula for figuring out what width tire will fit on the rim, a google search will find that, I think a schwalbe big apple is too wide on a GM 305 X 20 rim ,