BGM Lambretta crank 60 x 110mm

[coaster]

Is there anyway you can identify the bad batch apart from the oil seal shoulder issue?

As per the original post, use a vernier gauge and measure the drive side oil seal shoulder "!Best measure the shoulder where the seal sits, the BGM item measured 9.32/9.29/9.30mm

That then lead me to check other cranks Inocennti, MEC, Mazzucchelli, Omega and Indian which varied between 8.29mm and 8.48mm
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