To start with, if it is the bike i'm thinking (looking at one picture right now) it is a thing of looking at the picture to see that it takes a 1 inch threaded fork and a 1 inch jis or iso (who knows) threaded headset. U need to measure the headset "hole" to know if it takes a iso or a jis threaded headset.

1 1/8 headsets and forks came up to the market maybe like 5 to 10 years after that bike went out of production. Bikes aren't mekanos my friend, just do your home work better and use a lot of common sense. Like for example why did u get a 1 1/8 headset and fork when clearly using a caliper or a measuring tape the hole diameter of the headset area is 1 inch? Rule #1, to measure the stuff before buying.

Good luck

http://www.nice****ingbike.com/2009/07/schwinn-road/