Cup and Cone Hub Basics
By: Vaibhav Nijhowne
Also featured in Issue #7 | Jan 2012
What is one of the most important parts of a bicycle, in terms of movement? I’d say the wheels. What do the wheels revolve around? The hubs. So to reduce friction and ensure smooth and efficient functioning of our bikes, we need to frequently service and adjust our hubs. Many higher end bikes come with sealed bearing hubs which cannot be adjusted, but there are still a lot of regular cup and cone hubs in the bikes being sold in our local markets. So we thought it makes sense that we show you how to service and adjust these babies!
A cup and cone hub system consists of a hub with a cup built in to it. The ball bearings rest in this and a cone screws onto the axle and the ball bearings spin between these two. The tension can be adjusted by tightening or loosening the cone with respect to the bearings. The cone is kept in its position on the axle with the help of a locknut, washer and / or spacer.
If you do a lot of rough offroad riding, your hubs will benefit from frequent service. The best way to tell is to remove the wheel from the frame, take out the QR, and turn the axle with your hand. If you can sense any grit, sizeable friction or lateral play, then your hubs could do with a checkup!
Tools required to service the hub mechanism: Cone wrenches #15 and #17
STEP 1: Pry out the rubber dust cover from both ends of the axle
STEP 2: Loosen the locknut from the outer cone by the use of the cone wrenches and remove the locknut, washer, spacer and cone from the axle.
Note: you only need to open up the cone on one side of the axle.
STEP 3: Pull out the axle from the other side of the hub. The cone, spacer, washer and locknut are intact on this side of the axle.
STEP 4: Proceed to clean out all grease and dirt from the axle, cones, washers, locknuts and cups with a soft cotton cloth. Apply grease onto the axle and cones.
STEP 5: Pull the ball bearings out of the cups from both sides of the hub and clean the cups and the bearings.
STEP 6: Fill the cups with just the sufficient amount of grease to keep the bearings in place – too little will not protect, too much will only attract dirt.
STEP 7: Replace the ball bearings back into the cups on both ends of the hub inner. Ensure you’ve put the correct number of bearings on both ends.
STEP 8: Put a little grease on the bearings with your finger.
STEP 9: Slide the axle back inside the hub and then fit the cone back on from the other side of the axle till it becomes plush with the bearings. Tighten the locknut (and spacers) against the cone.
STEP 10: Turn the axle with your fingers and check that it is revolving smoothly. The cone should be tight enough against the bearings so there is close to zero lateral play. Too tight means the
bearings and cone / cup will wear out faster. Too loose and there will be play in the bearings which will damage the cone / cups. You may not always get this step right in the first go, so try it a few times until you’re satisfied you’ve got the right tension between the cone, bearings and cup. The simplest way to do this is to only make the adjustment on one side of the axle, since you have only opened the cone from one side.
STEP 11: Now tighten the locknut against the cone with the cone wrenches and make sure you don’t alter the position of the cone while you’re at it (otherwise you’ll ruin the bearing tension).
STEP 12: Put the dust cap back on > Go for a ride > Have fun > Have beer