Shimano Digital Hub Rebuild

Question: Your video on adjusting Dura Ace 9000 hubs is very useful, but I wanted to see if you could walk me through a full hub overhaul for my Ultegra 6800 hubs.

Answer: Ultegra 6800 and Dura Ace 9000 hubs use the same axle and cone layout, so the overhaul process is the same for both.

 

Start by placing a 5mm Allen wrench into each end of the hub and then back out the non-drive side lock nut, followed by the digital adjustment cap, and then the non-drive side bearing cone. Then the axle can be removed from the drive side.

Now that you have the axle off, use a magnet to remove the bearings. Then clean and inspect the bearings, cups, and cones. Look for pitting on all of the internals, especially on the cones, to see if any parts need to be replaced. If the drive side cone is damaged on the rear axle, you should replace the axle assembly. This is because the drive side lock nut is held in place with a very high strength threadlocker. Removing it is possible, but you will damage the axle in the process.

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To reassemble the hub, I like to start by applying a bead of Shimano Dura Ace grease to the bearing cup and then stick the bearings to the cup. This will hold the bearings in place when the axle is reinserted.

Slide the axle in from the drive side and then thread on the non-drive bearing cone until it is lightly finger tight, then install the digital bearing adjustment cap, followed by the spring washer, and then non-drive side lock nut. Torque the lock nut down to 15-17nm.

Check to make sure that the bearings aren’t too tight or too loose, adjust accordingly as shown in the other video, and you are good to go.

Welcome to our Ask a Mechanic column where our expert mechanics Daniel Slusser and Greg O’Keeffe answer your bike maintenance questions. If you have a question for us, please post it on the Art’s Cyclery Facebook Wall or e-mail Daniel directly at daniel.slusser@artscyclery.com. To see more great how to videos click on the highlighted link to subscribe to our YouTube channel and stay up to date on each episode of the Art’s Cyclery/VeloNews Ask a Mechanic Series.

2015-12-16T15:28:32-08:00