Hey guys, today I’m going to replace the bottom bracket
of this Trek 930
to Hollowtech II
The installation is very straight forward
if you get the right bottom bracket for the bike and crankset
Let’s start by removing the old crankset and bottom bracket
Which one is more durable?
Is lighter the better?
The old square taper bottom bracket is 382 grams
and the crank arms are 524 grams
This brings a total of 906 grams
The new Hollowtech bottom bracket is 98 grams
and the crank arms are 643 grams
This brings a total of 741 grams
The bottom bracket comes with 3 spacers
and each spacer measures 2.5mm
It fits both 68 and 73mm bottom bracket shells
with the right amount of spacers inserted
If you are not installing a chain guide
or mounted derailleur
Install only one 2.5mm spacer
The spinning has less resistance
with the new bottom bracket