Your frame was made by Giant (Taiwan) in April, 1985. The 1985 Le Tour, Traveler, and World Sport models all had 4130 chromoly double-butted main tubes. You should be able to tell which model by looking at the catalog photos and checking the specifications for the originally equipped components on each model.

1985 Le Tour catalog page

1985 Traveler catalog page

1985 World Sport catalog page 1

1985 World Sport catalog page 2

1985 Specifications page 1

1985 Specifications page 2

EDIT - Definitely a World Sport; I didn't see the flickr link.