I recently decided to repack the grease in my Shimano Ultegra front hub since it had not been done for a long time. It felt releatively smooth prior to repacking. I disassembled the hub and throughly cleaned everything. Put new grease in and carefully adjusted the cones. Now the hub is running very rough. I am sure the bearings are not adjusted too tight. A friend of mine suggested that if I mixed the bearings from the right / left sides that it could be the cause. I have not disassembled the hub yet to look for pitting. What else could cause this?
I recently decided to repack the grease in my Shimano Ultegra front hub since it had not been done for a long time. It felt releatively smooth prior to repacking. I disassembled the hub and throughly cleaned everything. Put new grease in and carefully adjusted the cones. Now the hub is running very rough. I am sure the bearings are not adjusted too tight. A friend of mine suggested that if I mixed the bearings from the right / left sides that it could be the cause. I have not disassembled the hub yet to look for pitting. What else could cause this?
Thanks - Joel
It could be caused by dust seals that got damaged if you tried to remove them, balls getting into places they shouldn't be, some kind of matter in the bearings that got in or got re-arranged, or damage of some type to the bearing surfaces. Did you check the condition of the balls? It's usually worth just putting new balls in whenever you do an overhaul, although there is much disagreement on this (personally, I've overhauled tons of hubs but have almost never re-used balls, so I don't know the ins and outs of doing so very well, but the mixed left- and right-side ball hypothesis doesn't make any sense to me).
I recently decided to repack the grease in my Shimano Ultegra front hub since it had not been done for a long time. It felt releatively smooth prior to repacking. I disassembled the hub and throughly cleaned everything. Put new grease in and carefully adjusted the cones. Now the hub is running very rough. I am sure the bearings are not adjusted too tight. A friend of mine suggested that if I mixed the bearings from the right / left sides that it could be the cause.
I find it hard to believe that right/left bearing wear would be sufficiently different to make such a problem occur. You seem to be talking about really apparent roughness. Possibly the other response suggesting a problem with the dustcaps is the answer. Or, maybe a hair or some grit got in the grease during re-assembly. Another option would be to question your certainty that the bearings are not too tight. There is a difference between the correct pre-load off the bike, and the correct pre-load on the bike. Quick-release hubs have to be adjusted a bit loose in order to account for the compression of the Q/R. I usually look for just a bit of play before I clamp the wheel onto the bike, in order to get no play and a smooth hub on the bike.
I do second the suggestion to not try to save a few cents by not replacing the bearings. Even with the best available (OK, forget ceramic, but grade 25 steel) bearings, you are talking about only $1 to $2 to replace rather than clean the bearings.
--
David L. Johnson
__o | Let's not escape into mathematics. Let's stay with reality. -- _`\(,_ | Michael Crichton (_)/ (_) |
I recently decided to repack the grease in my Shimano Ultegra front hub since it had not been done for a long time. It felt releatively smooth prior to repacking. I disassembled the hub and throughly cleaned everything. Put new grease in and carefully adjusted the cones. Now the hub is running very rough. I am sure the bearings are not adjusted too tight. A friend of mine suggested that if I mixed the bearings from the right / left sides that it could be the cause. I have not disassembled the hub yet to look for pitting. What else could cause this?
Thanks - Joel
Make sure 10 3/16 in each side, NOT 11...ideally, you should replace the balls at overhaul time. Really hard to reassemble wrong on this hub.
