Bottom Bracket Fitting

[Colin0912]

Hello im just fitted my new BB after a issue with the last and was wondering on how tight it should be should the crankset be able to move freely or with some resistance??

 

[Paulus]

It should move freely.

 

[Arjimlad]

The tightness of the fit of the bb, inside the frame, should not affect how freely the axle itself turns.

 

[chillyuk]

The last one I fitted, which was a genuine Shimano item, did have a very slight resistance, but was undetectable when peddling, and within a few miles freed off completely. I just put it down to a new item needing to bed in slightly. It has been no problem sisnce.

 

[guitarpete247]

Just get it tight then back off a tadge. If there is any excess movement side to side, up and down it needs a little nip up. If it feels like there is sand in the bearings back off a little. I've found it takes a bit of trial and error to get it right.
Then check again after a few rides and tighten up if needed.

 

[Zoiders]

If it's the old square taper BB with a cartridge bearing - then yes if you go too tight with the cup you can put sideways loading on the cartridge bearing between the races as the shoulder of the BB axle will put pressure on the central bushing and it will bind as you try to turn it.

Having said this most new BB's tend to be smooth turning but not as spinny from new as you would imagine.