Hollowtech II bottom bracket spacers explained

Should you put spacers on both the right and the left-hand side cups? How many spacers and which thickness?

I tried answering those questions along with explanations why.

CONTENTS:
00:00 Introduction
01:34 3 notes
03:07 3 goals
06:54 BB shell width and diameter
12:05 Threaded bottom brackets
15:47 2.5 mm "default" right spacer
18:17 Road bike BB cups
21:18 MTB BB cups
23:54 How to check if it's all good
27:17 Wider (boost) frames and press-fit
29:21 Catches and gotchas

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How to install Shimano Hollowtech II bottom bracket - video:
https://www.youtube.com/watch?v=0uS71UrROMc

What is a bicycle chainline and how to measure it? - video:
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Accurate vs precise, digital vs analogue - Calipers, how to use them? - video:
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Accuracy vs Precision - article:
https://bike.bikegremlin.com/8374/accurate-vs-precise/

Threaded bottom bracket standards, thread pitches, and diameters - article:
https://bike.bikegremlin.com/1634/bicycle-bottom-bracket-standards-explained/

Threadless (press-fit) bottom bracket standards and dimensions - article:
https://bike.bikegremlin.com/1652/press-fit-bb/

T47 threaded bottom bracket standard:
https://bike.bikegremlin.com/1672/new-threaded-bb-standard-t47/

Anti-seize (mounting) pastes and greases - video:
https://www.youtube.com/watch?v=Xb7NEbc3sUI

Mounting and anti-seize pastes - article:
https://bike.bikegremlin.com/7172/anti-seize/

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