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GuyContinental
06-07-2012, 10:21 AM
So- a little known fact: Apparently Shimano cassette bodies have a deeper spline clearance than required for most non-Shimano freehub bodies (thus, they can fit virtually any freehub whereas the opposite isn't necessarily true). As a result, unless you are using a Shimano freehub body you will likely have clearance on top of the freehub spline when using a Shimano Cassette. I don't really get the physics of it since the width is fine, but over time a Shimano cassette will dig into the freehub body and creating play which then causes it to dig in even deeper (See attached photo). On the pictured bike my cassette is now so dug in that it's a) unremovable and b) starting to mess up my indexing.

1166

I've never actually had one stuck before (and this one is reallllly stuck)- does anyone have any suggestions for getting it off? Once I get it off I can file the splines but I bet that the freehub will just fail again. Are freehub bodies interchangable? (i.e. can I just buy an Ultegra body and swap it on my Williams hub?) I've never really messed with freehubs before and can imagine springs and bearings going everywhere... any advice from the best and brightest?

jabberwocky
06-07-2012, 10:25 AM
I've always just used a chainwhip and twisted the cassette in the opposite direction to pull it out of the grooves, and then slid it right off.

Just file it down and keep using it. That goes with the territory with alloy freehub bodies. Yours isn't even half as bad as some that I've had. :)

Tim Kelley
06-07-2012, 10:30 AM
This happens to me all the time on my powertap hubs. I attribute it to my massive quads and have subsequently upgraded from alloy freehub bodies to steel ones.

Tim Kelley
06-07-2012, 10:33 AM
I've never actually had one stuck before (and this one is reallllly stuck)- does anyone have any suggestions for getting it off?

If regular tools fail, use a hammer and screw driver to lightly tap it out of place. You'll find the cog that is stuck is probably your favorite that you ride in the most, or use to lay down serious power on climbs or sprints.

jabberwocky
06-07-2012, 10:46 AM
Just to give a little more detail:

This is due to two factors: a cassette with individual cogs (not mounted on a carrier) and an alloy freehub body. When the cogs aren't on a carrier, they can twist individually and are thin enough to then dig into the soft aluminum of the freehub under power. Its happened to every aluminum freehub I've ever owned. The solution is to either purchase a hub with a steel freehub or get cassettes that mount the cogs on a carrier.

To remove the cassette, wrap the larger cogs in a towel (so you can grip them), and then put your chainwhip on the smallest cog and twist it to pop it out of the grooves its dug in the freehub and then slide it off. Repeat until you get to the larger cogs (which are usually on a carrier and shouldn't be dug in as bad if at all). You may need to file the freehub to get the larger cogs and their carrier off the hub easily.

And yes, the freehub is usually replaceable (depends on the mfg). But looking at yours, its not nearly bad enough that I'd replace it. I'd just get everything off, file the freehub smooth and put it back on.

Dirt
06-07-2012, 10:56 AM
Most wheel companies that make alloy freehub bodies suggest using cogs that have a carrier, rather than individual cogs... even the ones bolted together.

Getting a replacement freehub body will likely have to come from Williams, unless you know who their hub supplier is. Many companies like that use Novatec hubs, thought he Williams hubs look different from the Novatecs that I've seen.

A shimano freehub body will probably not fit.

It doesn't look like you have anything to worry with. Like Jabberwocky said, we've had much worse than that and ridden them for ages.

If you get a cogset that has an alloy carrier for the cogs, you may find that you need to very carefully file off any burrs that have been created. The carriers tend to fit a little tighter than the cogs with individual cogs.

GuyContinental
06-07-2012, 12:56 PM
Ahhh- this is an Ultegra cassette with a carrier for 8 of 10 gears not individual cogs. Also- that photo was 4 months ago... now it's really bad. The whole carrier is jammed on and I haven't been able to dislodge it with a whip or even a screwdriver.

Dirt
06-07-2012, 01:20 PM
Ahhh- this is an Ultegra cassette with a carrier for 8 of 10 gears not individual cogs. Also- that photo was 4 months ago... now it's really bad. The whole carrier is jammed on and I haven't been able to dislodge it with a whip or even a screwdriver.
Williams would be a great source of information for you. I've always got good response from them with tech questions about their wheels.

Worst case, you can get a new freehub body and a set of cogs that they recommend as working better with their freehubs and replace both. You don't need to remove the cogs to change the freehub body. That is worst case.

jabberwocky
06-07-2012, 01:42 PM
I don't believe Ultegra cassettes actually have a carrier. At least, the one I have doesn't (its 10 speed but a few years old). It has individual cogs pinned together. Maybe the newer ones have a carrier. I've never actually seen a carrier dig into a freehub body.

GuyContinental
06-07-2012, 01:55 PM
Sorry- you are correct, they are pinned.

DaveK
06-07-2012, 03:17 PM
I attribute it to my massive quads

You attribute everything to your massive quads.