Joined: Jun 2006
Posts: 1,438
Likes: 194
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!
Sometimes the inner threads, especially if the previous cup was "short", can get rusty or filled with gunk, making it hard to thread newer cups on.