Noisy Or Creaking BB30 Bottom Bracket Bearings

As with any bearing they will wear out, due to use, dirt or water ingressed.

But if your bearings are not lasting long, then you need to look further...............

To help prolong the life and stop any creaking your BB30 bearings they need to be fitted correctly in the first place.

There can be two press fit complications with the BB30
  1. It is likely from the press fit being too tight: If the fit is too tight, it can be corrected by reaming the frame shell. A professional Cycle Tech Mechanic will use the Park Tool HTR-1 and the 752 BB30 Reamer Set. This will correct the inside diameter by removing material from the shell.
  2. The press fit into the frame is too loose: The bearings may move in the shell when stressed by pedalling. This results in a creaking sound. To resolve this, first check the torque on crank bolts to determine if the crank-to-spindle interface is the source of the noise. If this fails and there is still creaking, it may be the cartridge bearing moving in the shell. The bearings should be removed and new ones installed. Press the new bearings into the frame using a retaining compound such as Bondloc B641 Bearing Fit Retaining Compound.
Note: The Bearing shell outside diameter 42mm. Parktool Reamer diameter 41.94

Bondloc B641 Bearing Fit Retaining Compound

There can be three press fit complications with the PF30

PF30 Cartridge bearings are mounted into either plastic or aluminium adaptors
  1. It is a good idea to press the PF30 bearings into the shell with retaining compounds or at least a threadlocker. However, because most of the PF30 bearing adaptors are plastic, the retaining compounds will generally not set up and harden. Use special "Loctite Primers" that allow the compounds to harden.
  2. If the press fit is too tight, it will squeeze the bearings and result in premature wear, similar to problems in the BB30 system.
  3. If the bearings seem to wear prematurely, it may also be the result of uneven shell faces (opposite shell faces not square). These can be faced to improve bearing alignment, similar to how headset faces are designed. The process can allows a face-only option of the outer surfaces of the frame shell. A professional Cycle Tech Mechanic will use the HTR-1 and the 791 Reamer Set. This can improve alignment between the two bearings, resulting in greater smoothness and longer bearing life.
Note: The Bearing shell outside diameter 46mm. Parktool Reamer diameter 45.94

Broken bearing inner ring on crankshaft axel 

Old bearing and ball races
 
Crankshaft axel cleaned and new seal fitted
 
 Circlip removal/fitting
 
Parktool bearing press 

 New bearing fitted


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