Joined: Jun 2006
Posts: 1,434
Likes: 191
From: SW Virginia
Bikes: 62 Falcon, 58 Raleigh Lenton Gran Prix, 74 Raleigh Pro, 75 Raleigh Int, 75 Raleigh Comp, 76 Colnago Super, 75 Crescent, 80 Peugeot PX10, plus others too numerous to mention!
Shimano "SF" dropouts were used on some higher-end Trek bikes in the early 80's(710's for instance). With Shimano dropouts in the rear and Tange drops in the fork, it is highly likely the fork is a replacement. These chrome Tange forks are fairly common replacement items.