# Cassette "wobble" problem



## gtpharr

I've noticed a problem with one of my rear wheels. The wheel is a Velocity Deep V rin with Shimano 105 hub. 

When the bike is on a workstand with the freehub engaged (wheel is spinning and cassette is stopped), I'm seeing some "wobble" in the cassette.

I have 3 rear wheels & 2 bikes and have rotated wheels around in an attempt to isolate the problem. I've been able to positively determine the problem is specific to this 1 particular wheel and is not a problem with the bike.

I removed and re-installed the the cassette to ensure the 1mm spacer is in place. The cassette lock ring is properly torqued to 40 n-m and the "wobble" is still present.

When properly installed and torqued on the freehub, I noticed the cassette had a very small amount of play in it. I checked my other 2 wheels and they both had a similar amount of play between the cassette and freehub. However, these other 2 wheels do not have a problem with cassette "wobble".

When using the rear wheel in question, my rear shifting is rather inconsistent. Sometimes it is so smooth that you can hardly feel the shift and other times it feels like it was hit with a hammer. I'm now wondering if this "wobbling" cassette may be the cause of my inconsistent shifting.

My questions are:

1. Is some of amount of cassette "wobble" normal or acceptable? 

2. Is is normal for Shimano cassettes to have any amount of play in them when properly installed and torqued on a Shimano hub? I have 3 rear wheels (all Shimano hubs & cassettes) and all 3 have very slight amount of play in the cassette when the wheel is off the bike.

3. Could the cassette be the cause of my "wobble problem"? I have not swapped cassettes between 2 of my wheels, but I could do that if anyone thinks it will help isolate the problem. 

4. Assuming the "wobble" is not normal, what is the most likely cause of the problem and suggestions for corrective action?

Thanks for any help you can provide


----------



## Sloburu

I have the same problem with my shimano rs-80 wheels. Shifting is no problems. It's only some noise.


----------



## valleycyclist

Maybe the axle is bent. A replacement axle for a 105 hub is inexpensive.

In terms of play, I never noticed any play with cassettes.

EDIT:
Also make sure the freehub body is properly secured to the hub (need a 10mm allen wrench)


----------



## gtpharr

I spoke with LBS and the guy who built my wheels. Both say what I am seeing is known as "cassette oscillation". The both said it is not uncommon and nothing to worry about. They both said forget about it and go ride the bike.

I also spoke Shimano Tech Services. The Shimano rep knew exactly what I was talking about and said that it is not normal or correct. The Shimano rep said the freehub may be loose or need replacing. The Shimano rep said this problem causes inconsistent/erratic shifting which does seem to be the case with my bike.

I'm not sure who to believe.


----------



## valleycyclist

gtpharr said:


> I spoke with LBS and the guy who built my wheels. Both say what I am seeing is known as "cassette oscillation". The both said it is not uncommon and nothing to worry about. They both said forget about it and go ride the bike.
> 
> I also spoke Shimano Tech Services. The Shimano rep knew exactly what I was talking about and said that it is not normal or correct. The Shimano rep said the freehub may be loose or need replacing. The Shimano rep said this problem causes inconsistent/erratic shifting which does seem to be the case with my bike.
> 
> I'm not sure who to believe.


It is pretty easy to verify that the freehub body is secure. Remove the cone on the non-drive side (need a 14mm and 15mm cone wrench), slide the axle out, and then use a 10mm allen wrench on the freehub body and verify that it is tight.

If it is causing shifting problems then it is not normal.


----------



## PoorCyclist

I also asked about this before, but people are thinking I am being too picky and obsessed.
Mine wobbles when it is coasting or back pedalling, but when actual power is applied in the forward direction it is not noticable, I was told it has to do with pawl engagement, when pedalling forward everything is engaged properly and no wobble... Anyway no problem with shifting..


----------



## penn_rider

I have notice oscillation before, common, but if you ar having shifting problems and all else has been adjusted then check the free hub body.


----------



## Sloburu

valleycyclist said:


> Maybe the axle is bent. A replacement axle for a 105 hub is inexpensive.
> 
> In terms of play, I never noticed any play with cassettes.
> 
> EDIT:
> Also make sure the freehub body is properly secured to the hub (need a 10mm allen wrench)


Are you saying the skewer might be bent?


----------



## Kerry Irons

*Get bent*



Sloburu said:


> Are you saying the skewer might be bent?


No, he said what he meant and he meant what he said: the axle might be bent. Not the most probable source of this issue, but a possibility. If the axle were bent, you could feel the bearings bind as you turn the axle with your fingers (light touch).


----------



## steve_e_f

my oscillation was coming from using an incorrect spacer between the cogstack and the inner edge/rim of the cassette body. the spacer's diameter was too large so when the cassette was tightened onto the casette body, it sort of "rode up" on the ridge a little bit in an uneven manner until it was tight. The uneven connection between the two caused the wobble wobbled. by putting the correct spacer on there the cassette sits perfectly tight and flush against the cassette and there is no wobble now.

This actually a bit tough for me to describe accurately, hopefully it makes sense.

bottom line, if you use one of those spacers on the inside edge of your cogstack/cassette make sure it fits perfectly.


----------



## gtpharr

I stopped by 2 more shops and they took a quick look at my bike. The mechanics at both shops seemed pretty knowledgeable and caring. Both said the cassette oscillation is very normal and common. They said many bikes do this and it is nothing to worry about. 

One of the mechanics pulled 3 new bikes off the floor and checked them. 2 out of 3 bikes had some visible oscillation in the cassette.

It appears the cassette oscillation I'm seeing on my bike is pretty common and nothing to be concerned about.


----------

