# Shimano cassette noise



## shudson16 (Mar 20, 2009)

I started noticing noise coming from my cassette and have isoloated it to the cassette body. It makes a gritty sound but only at a certain point and when at that point I can feel it and see it actually pulling on the crankarm. It acts like it's out of round and one point is rubbing against something. I can't feel/hear it when riding just when I have it in the stand. Are these things repairable and if so are they worth repairing or should I just replace the whole thing? It only has about 2k miles on it. I'd think it would last longer than that. It's a Shimano CS-HG50 so it's nothing high-end. What say all?


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## Uncle Grumpy (Jul 25, 2005)

The cassette isn't the problem, it's the hub. Other than wearing the teeth or bending a sprocket, not much can go wrong with a cassette, they are an inanimate lump of metal.

However, the slip onto a part of the hub which is comprised of intricate ratchets and pawls which.

What sort of hub is it (make and model)? You can replace the freehub body so it's not as if you need a new wheel.

But... the issue at hand is kind of the point here. Not sure what you mean when you say it's pulling on the crank. You mean, there is noticeable resistance at one point?

Check the sprockets to see if any have bent. Also check to see the cassette is on right and not sitting skewed, or the wheel is in the frame right and not sitting skewed.

The cassette isn't loose?

You say it feels like it's rubbing on something? Well, is it? Is something rubbing on the frame? Is it happening in all gears?

Grumps


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## Uncle Grumpy (Jul 25, 2005)

Oh also, does the rear wheel still make the ratcheting sound when freewheeling, or has it gone silent?

Grumps


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## JimP (Dec 18, 2001)

*More questions*

Does the cassette make noise in all gears? Is the RD aligned with the gears of the cassette? Does this noise happen when pedalling forward or backward?


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## shudson16 (Mar 20, 2009)

Uncle Grumpy said:


> The cassette isn't the problem, it's the hub. Other than wearing the teeth or bending a sprocket, not much can go wrong with a cassette, they are an inanimate lump of metal.
> 
> However, the slip onto a part of the hub which is comprised of intricate ratchets and pawls which.
> 
> ...


Shimano WHR-500 wheelset

yes. If you hold the crankarm w/ your right hand and turn the cranks very slowly you will eventually hear a grinding sound.. and when that happens you can turn the cranks backward ever so slow and you can feel resistance and see the resistance actually try to move the cranks.

the cassette is not on crooked. it's never been removed since I bought the bike. This noise issue just started like a couple of days ago. Prior to that everything was ok. I've taken the cogs off the freewheel body but have never removed the freewheel body from the hub itself.

no

The rubbing is an internal rub, inside the cassette.The wheel sits properly in the rear triangle of the bike. At first I thought it was a brake pad rubbing or perhaps an out of true wheel but it's none of things. I've also checked to make sure the is ample clearance between derailleur cage/pulley,etc and there is. Doesn't matter what gear it's in but it tends to be more noticable in the larger gears, i.e. Large chainring/smaller rear sprockets


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## shudson16 (Mar 20, 2009)

backwards


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## shudson16 (Mar 20, 2009)

Uncle Grumpy said:


> Oh also, does the rear wheel still make the ratcheting sound when freewheeling, or has it gone silent?
> 
> Grumps


 still makes the ratcheting sounds.


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## FBinNY (Jan 24, 2009)

When you say you can see it pulling on the crank arm, do you mean that when coasting, the cassette body (or freehub) sticks and tries to push the chain around?

If so, combined with the sound you describe, I'd suspect rust and/or dirt in the ratchet mechanism, the freehub bearings, or caught in the seal area. Regardless the cure is the same, Fieldstrip the cassette body, clean and examine the areas involved, lube and re-assemble. Freehubs do last forever with decent care, but are prone to contamination and so require periodic service.


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## JimP (Dec 18, 2001)

If it only makes the noise when pedalling backwards, does it make it in all gears? There isn't a RD to guide the chain onto the sprocket when pedalling backwards. I suspect the issue is a chain line problem and the noise is most noticeable when in the largest sprocket. If this is the case, I wouldn't worry about it.


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## shudson16 (Mar 20, 2009)

OK guys, I got it fixed. There are two seals on the freehub, one on the backside, which is basically a rubber o-ring that covers the bearings. The other is on the front side and is made of metal. I removed the front seal and found scuff marks around part of the inside surface. Evidently the seal got pushed in further than where it was supposed to be ( was not sitting square inside the body) and in turn was scraping against the freehub body when it turned. It was real obvious. I remounted it, greased it up good and the noise is no longer present. How it got pushed in is a mystery to me but I'm back on the road again, quietly I might add. Learn something new everyday, huh.


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