Joined: Jan 2009
Posts: 44,123
Likes: 6,340
From: New York, NY, and High Falls, NY, USA
Bikes: 1962 Rudge Sports, 1971 Raleigh Super Course, 1971 Raleigh Pro Track, 1974 Raleigh International, 1975 Viscount Fixie, 1982 McLean, 1996 Lemond (Ti), 2002 Burley Zydeco tandem
According to my imperfect eyes, that thread pitch gauge does NOT fit well onto the threads. I think you have a 24 tpi cup, so you need English threads.