Figure 7-4: A cup-andcone hub in .NET

Maker Quick Response Code in .NET Figure 7-4: A cup-andcone hub

Don t be fooled by the label sealed mechanism These are standard cup-andcone-style bearings, except they have a rubber seal to help keep contaminates out They aren t true sealed bearings

Well-functioning hubs are critical for smooth spinning wheels and a comfortable ride To keep your hubs in the best possible shape, plan on overhauling the hubs at least once a year If you re lucky enough to have sealed-bearing hubs you re off the hook; most of these will last many years without any service If you have cup and cone hubs, follow these steps: 1 If you have a quick-release skewer, remove it from the wheel If there are nuts on the hub remove them with a wrench, alternating side to side as you loosen

2 Using a cone wrench and a second standard wrench, make sure the cone and locknut are tight against each other on one side of the hub 3 On the other side of the hub, using a cone wrench, secure the cone in place while you loosen the locknut in a counterclockwise direction on the same side of the hub (see Figure 7-5) It will usually require some force to initiate movement in the locknut If you re working on a hub with a freewheel, remove the freewheel (see 11 for instructions) If you have a cassette hub, work on the side opposite the cassette 4 Remove the locknut, washers, and cone from the axle, keeping them in order as you remove them 5 Hold a towel or cup under the hub as you pull out the axle, because some bearings may fall out Figure 7-6 illustrates the removal of an axle Leave the cone, washers, and locknut in place on the other side of the axle This will make reassembly easier 6 Using a screwdriver, remove the bearings from both sides of the hub (see Figure 7-7) A magnetic screwdriver makes bearing retrieval easier, although a screwdriver tipped with grease will work Another trick is to push them down through the center of the hub and out the other side

Count the bearings in the hub Some hubs are designed for ten bearings in the front and nine in the back Because you ll probably want to replace the bearings with new ones (they re cheap), you ll want to know how many to purchase (and how many to use for reassembly) 7 After the bearings are removed, wipe the inside of the hub shell with a cloth and then use a degreaser to clean the cups Examine the cups for wear If they have dents in the surface, you may need to replace the entire hub 8 Clean the axle, nuts, and cones by removing dirt and grime from the threads Examine them for signs of wear and tear If you roll the axle across a flat surface and it wobbles, it may be bent and need replacing 9 Wipe down the dust seals with a cloth If they re especially dirty, you can pop them off using a screwdriver for leverage 10 After cleaning all parts, allow them to dry thoroughly before reassembly

When you re all done overhauling the hubs, it s time to reassemble them To reassemble the hubs, follow these steps: 1 If you removed the dust seals, press them back into place 2 Apply a fresh layer of grease to each of the cups (as shown in Figure 7-8) The general rule is to use enough grease so that a bearing will be covered halfway when placed in the cup 3 Using tweezers or pliers, place half the bearings in one cup, spreading them out evenly across the cup (as shown in Figure 7-9) The bearings should be held in place temporarily by the grease Make sure there is at least a 1mm gap between all the bearings placed in the cup If the bearings are too tight, remove one, so that each bearing has a few microns of elbow room 4 Grease the axle and slide it halfway into the hub to hold the bearings in place while you fill the other cone with bearings Make sure that no bearings fall out during this procedure