Mountain bike crank spindles are for 73mm frames, so they need spaces for 68mm frames. Shimano road crank spindles are for 68mm frames. A BSA (normal British threaded) bottom bracket, doesn't need any spacers, you just thread the cups on and then put the cranks in.
Where do the spacers go on a bottom bracket?
For a bottom bracket shell width of 89.5mm, insert the 2.5mm spacer into the right hand side (between the frame and the right hand adapter). Use the inner cover. bottom bracket shell, it should be installed with the inner cover sleeve to prevent possible contamination.
How do you use a bottom bracket spacer?
https://www.youtube.com/watch?v=hcToKhQwUJY
Are bottom bracket spacers necessary?
If you need to use a bottom bracket mounted chain guide or derailleur, then you'll also need to remove the innermost 2.5mm spacer on the drive side - so a 68mm or 83mm shell will have one drive side spacer and one non-drive side spacer, while a 73mm shell will need no spacers at all.
Do dub bottom brackets come with spacers?
Both have the same bb, just different spacers. Normal one come with a 3mm, to be used with normal Dub crank. Wide one come with 2.5mm and 5.5mm spacers, to match with wide Dub crank. "One Color 68/73" is for standard Dub crank (come with 3mm spacer.)
Does any crankset fit any bottom bracket?
Crankset compatibility In general terms, most cranksets can be fitted to a variety of bottom bracket shells, though much of this compatibility depends upon the availability of suitable hardware (see next section). Any incompatibilities that do arise are often related to the length and/or diameter of the crank axle.
What do I do if my bottom bracket is loose?
Firmly hold the bike steady and attempt to move the crank from side to side in the opposite plane of motion to its rotation. If there is any play from side to side, the BB system is loose. An open/loose BB will need its bearings adjusting (via the adjusting cup) or replacing.