To remove the old bearings, place the cup on a suitably sized socket to support the cup, bit with sufficient clearance to allow the cartridge bearing to fall out.
Use a parallel drift to tap around the inner race until the cartridge comes free. Tapping the inner race will probably result in damage to the old bearing but as you are replacing them this doesn’t matter!
Once removed, clean the cup. |
To fit the new bearing, place it in the cup and ensure that it is correctly aligned.
Then place the cup and bearing in a vice with protected jaws and ensuring that the bearing is still aligned, close the vice until just a small amount of the bearing is still visible. |
To drive the bearing fully home, select a socket that will contact the outer races, but not damage the cup or the bonded rubber on the cup that forms part of the primary seal.
Place the socket and bearing assembly in the vice and close again until a solid resistance is felt. This is the bearing fitted. |
Now just place a little grease around the secondary seal and the bonded rubber on the cup before gently pressing the plastic primary seal back in using the vice to keep it parallel.
Screw the cups back into the bottom bracket, torque up and reassemble the crank and axle assembly. |
You have just saved yourself £20 and up graded your bearings.
You can ask for stainless steel bearing which will offer even greater longevity, but these will cost around £22 each. |
Any questions on this, feel free to email me |