I was setting up a new Park Tool TS-4.2 and realized my whole process for facing a bottom bracket shell changed

I used to just chase the threads and call it good, but after reading a tech note from a frame builder in Portland, I now always face the shell first to make sure the bearing surfaces are square. Anyone else run into this or have a different order they swear by?

3 comments

3 Comments

iris_mason882mo ago

That Portland tech note got a lot of us. Facing first is the only way to be sure the bearing seats are true. Chasing threads after can mess up that fresh face. It takes more time but the crank spins smoother. Never going back to the old way.

henry_webb682mo ago

Oh man, telling me. I learned that the hard way on a rebuild last year. I was in a rush and chased the threads first like I always used to. Put it all together and had this weird high spot, just a tiny bit of bind you could feel. Had to pull it all apart again and start over facing first. Felt like a total rookie move, wasted a whole afternoon. That tech note is gospel now.

patriciaellis6d ago

Same rule applies to cooking... prep right or eat regret later.