Bearings on unicycles generally last a long time. Even when you take your unicycle in a fountain, or the sea, or just splashing around in the mud. They do give up in the end though, normally at the worst moment possible (like a race) you will hear them grinding first, then when you turn the wheel slowly by hand you can feel the restriction in the movement and a slight detent.
This is to give you a guide of what to do if you are brave enough to try and replace them yourself. Be warned this is not an easy task and requires special tools, most bike shops will be able to do this for you. What you will require:
- Replacement bearings - see our catalogue for quality replacement bearings.
- Crank extractor - again we sell these.
- Socket set - not really necessary, normal wrenches can do but makes it easier.
- Rubber hammer/mallet - again not really necessary, a little imagination can find other things that will do.
- Bearing puller - either as small 2 or 3 leg bearing puller - this is essential.
- Scrap of wood or Block - not really necessary but it helps to prevent damage and get accurate fit.
To remove and fit bearings:
1. Remove the dust covers from the cranks if you have them.
2. Remove the nuts/bolts from the center of the cranks
3. Remove the cranks using a crank extractor (see instructions). Be sure to screw the extractor all the way fully before you start to extract the cranks.
4. Remove the wheel from the frame, in most cases this involves removing 4 bolts from the bracket that surrounds the bearing. In the case of the Lollipop bearings the screws are in the side of the fork legs and the bearing holder stays with the bearing.
5. Fit a 2 leg or 3 leg bearing puller over bearings and use a wrench to pull the bearing from the hub. Be sure to seat the legs of the bearing puller securely under the bearing so that it is not destroyed before it is removed from the hub. On a lollipop bearing you need to extract the whole bearing holder. Do not try to remove with a lever or screw driver behind the bearing, it will damage the hub. For ISIS hubs use the ISIS cap from the crank extractor or something similar to prevent the bearing puller damaging the threads in the hub.
6. Once the bearing has been removed, clean the hub shaft with steel wool and little oil to remove any rust or dirt.
7. Put the new bearings over the shaft (be sure to fit spacer on first if one was fitted) and gently push, ensuring that it is square with on the axial. When it can not be pushed any further by hand place the old bearing on top of the new one and slip a pipe or socket on top. Ensure that the pipe/socket is pressing on the center of the bearing race, not the outer ring or rubber seal. Place the wheel on a piece of scrap wood to protect the other side of the hub axial. Hit the pipe/socket with a hammer until bearing is seated. Remove the old bearing.
8. Clean the bearing holders to be sure that there is no dirt or rust.
9. Re-fit the wheel in the frame. Be sure not to over tighten the bearing cups as this will impede the performance of the bearing.
10. Re-fit the cranks on the hub. Be sure to check that the cranks/pedals are on the correct side. On the end of the pedals there is a letter L or R for left and right and a letter on the back or front of the cranks.
11. Place the unicycle on your scrap of wood and use a rubber mallet to hammer the cranks on setting the pressfit (for cotterless and ISIS cranks only).
12. Tighten the nuts/bolts in the end of the hubs, these must be secure. Tighten snug, but do not over tighten.
13. Replace the plastic dust caps if you have them.