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Friend has a new steel frame. Top cup bearing fits nicely when assemble out the frame but binds when in.
Given the name you would think the headrube to be 44mm diameter, and the headset slightly bigger. However headtube I'd measured at various points is as follows-
43.38
44.70
43.80
Is this ovalised or requiring reamed/faced? 44.7 seems to be on the big side..
I haven't seen it and it's a shop that have provided the measurements, not sure if they have a confident diagnosis yet..
A new frame should not be ovalised - that happens if you run a headset loose. It might have been squished in transit perhaps but it needs to go back. a differnce of over a mm is well out of tolerance IMO
Head tube could have been damaged in transit, it could have also been distorted when welding.
Park Tool 788 reamer for ZS44 head tube reams to 43.95mm ID, for headset cup OD 44.05-44.1mm. Its not uncommon to have to ream frames that are too tight.
I would not be happy with the 44.7mm though on a new frame. If it was a free frame I would probably ream it and install the cup with a retaining compound.