Hello Zhaokun,SRAM engineering has contacted us with questions about uneven seal rubbing that has been noticed on the HYQ style DUB bearings for the new sizes in the Project Ceramic series. This specifically pertains to PN 62-6418-006-020, but may be the same for all 3 in this series.You can see from the customers comments below and the example of the torque tests that the C HYQ F2 6806 type has shown to have an irregular drag curve. This uneven feel is within the required torque specification, but with these high end cycling products, the “out of the box” feel is very important. Troy from SRAM claimed that the feel when rotated by hand was noticeable rubbing or unevenness. SRAM thinks this might be the seal. Can your team have a look at this and give your thoughts to the cause of this rubbing sensation. SRAM is also asking if we can determine a cause, can it be eliminated in production or sorted after production? If so, what is the cost impact.