Dura Ace wheel bearing factory grease

[dekindy]

My riding buddy is certain that since my Dura Ace hub is almost silent and that I am occasionally experiencing a "slippage" sensation that the grease is packed too tightly from the factory. I can only describe the slippage feeling as feeling like the chain is not aligned properlmy in the rings and then goes into place with a jerk. It does not feel like it is coming from the rear area like it is a cassette, hub, or derailleur area. But my buddy says that he has experienced the same thing and the rear hub being over greased is the cause.

My buddy says that if I have my LBS unpack the grease and then grease it more lightly that the wheel will roll better and the slippage problem will go away. The wheels are model 7850SL and have several thousand miles on them.

Any observations. The LBS service writer, not one that I normally deal with, identified wear on my large and middle chain rings so those and the chain were replaced but the problem is unchanged.

[AndrewS]

He sounds like he's on to something. That is how it feels when the pawls don't catch. Though with that many miles without problems, I'd say contamination or wear are more likely to be the problem than the grease viscosity alone. Either way, they probably should be looked at.

Lighter grease in the freehub won't make the hub any faster, though. But that's not really important.

[rnhood]

My Shimano wheels do the same thing. There was a thread on the Weight Weenie forum about this a year or two ago and, it is a very common occurance. I spoke to Shimano about it and they were aware, but assured me that nothing was at risk. The pawls just skip a beat every now and then for whatever reason. I've got two years and about 5K miles on one set of 7850 wheels and they still perform perfectly well (just like they ride).

[Pyramor]

Has anyone experienced this with Mavic hubs? I have a Classics Pro rear wheel on my Lemond Zurich. I don't know what model hub, but it uses straight pull spokes. Once about every 50 miles there is sudden jerk. I thought that it may be the chain (8 sp) but I can't find anything wrong with it.

[stephenmarklay]

I have heard of this (on Shimano factory wheels you have) as well. I wonder if less grease would help. Sounds like it might be worth a shot anyway.

I have the 7850 TL but have not ridden them yet.

How often do you experience this? Every mile? Every ride?

[PaulE]

If you are experiencing slippage in the rear hub, it is how the pawls are engaging in the freehub. How the wheel bearings are packed has no impact on this slippage you're feeling. When coasting, Shimano freehubs are much quieter than other hub brands such as DT Swiss, Mavic or White Industries. Also, Shimano freehubs cannot be disassembled and serviced by mere mortals. I am sure there are those who can do it, but the Shimano freehub design has loose ball bearings, different than Mavic or White Industries, 2 other brands I am aware of whose freehubs use sealed bearings and are relatively easy to disassemble to clean and lube the pawls.

You can try servicing your freehub with a Morningstar Tools Freehub Buddy (http://morningstartools.com/freehub_buddy1.html). After you flush out the freehub, lube it up with their Freehub Soup and use one of their replaceable Dust Shields. If you go this route, you'll need the Dust Shield as the Shimano dust shield will most likely be destroyed in the process of removing it.

You can also ask your bike shop if they can do this for you, but they may not be familiar with the Morningstar Tools products.

[dekindy]

Defintely not every ride, but occasionally. Once in a while it will be so violent that it causes my front derailleur to jam/catch. The last time it happened even though I was riding in a straight line it caused my front under to shimmy violently like cyclists describe when they are going downhill at high speed. Most times it is just a slight jerking and inconsequential. I would rather not have it. I wonder if the Campy 2-way fit wheels have any problems like this. May be something to consider when considering tubeless designed wheels.