Cassette wobble

[Vapin' Joe]

The OP stated that the cassette was wobbling while it was stationary and the wheel was spinning.

That's a bent spindle.

 

[summerdays]

So how do I check the spindle and would I have got a new one when the wheel was put on? Has the spindle an alternative name - I'm looking at my book and I can't quite work out what it is.

 

[Zoiders]

The OP stated that the cassette was wobbling while it was stationary and the wheel was spinning.

That's a bent spindle.

The spindle and the screw on freehub are not connected

The screw on free hub screws on just like a track sprocket to a fixed hub, accept its got the freewheel gubbins inside it

A bent spindle can cause uneven wear and then a wobble, but a bent spindle would not in itself cause the freehub to wobble when you spin the wheel backwards

 

[Vapin' Joe]

The spindle and the screw on freehub are not connected

The screw on free hub screws on just like a track sprocket to a fixed hub, accept its got the freewheel gubbins inside it

A bent spindle can cause uneven wear and then a wobble, but a bent spindle would not in itself cause the freehub to wobble when you spin the wheel backwards

Yes it would. The sprockets would not wobble if you just spun the freehub backwards with the wheel stationary, but he hub is rotating on the spindle and if the spindle is bent the hub and anything on it would move up and down as the wheel goes round.

 

[Zoiders]

Yes it would. The sprockets would not wobble if you just spun them backwards with the wheel stationary, but he hub is rotating on the spindle and if the spindle is bent the hub and anything on it would move up and down as it goes round.

Pick bike up, spin back wheel

Freehub will wriggle from side to side a bit, some do it even with a straight axle

I was mixed up with backwards bit, what I am saying is that if you let the wheel free wheel you will see the free hub wobble even though it is stationary

Some do it because of wear, some do it because the thread is not spot on

I know this because I have seen it happen on lots of old bikes

The spindle being bent would make the whole lot move, you wouldnt see movent of the freehub in relation the to hub body when stationary though unless the freehub itself had become worn

 

[Vapin' Joe]

Pick bike up, spin back wheel

Freehub will wriggle from side to side a bit, some do it even with a straight axle

I was mixed up with backwards bit, what I am saying is that if you let the wheel free wheel you will see the free hub wobble even though it is stationary
Some do it because of wear, some do it because the thread is not spot on

I know this because I have seen it happen on lots of old bikes

The spindle being bent would make the whole lot move, you wouldnt see movent of the freehub in relation the to hub body when stationary though unless the freehub itself had become worn

As it would do that if the spindle was bent, as even though it is stationary it is still sitting on the rotating hub.

 

[Zoiders]

No it wouldnt

You are just wrong

There is no direct interface between a SCREW ON freehub and the spindle

They dont touch, the wheel and the freehub would both move together in harmony in the same eccentric manner to the spindle, you would not see movement of one in relation to the other though.

I bent spindle would in the end cause it wear though, then you will see a wobble, it will continue to wobble even if you replace the spindle

 

[Vapin' Joe]

Let's make sure we are singing from the same hymnsheet here. I assume that what the OP means is oscillation of the sprockets rather than side-to-side play.

In which case there doesn't have to be a direct interface between a screw-on freewheel and the spindle for it to run out of true, because the sprockets are sitting on the hub and that will move up and down as it runs round a bent spindle.

 

[Zoiders]

Yes but it will not move in relation to the hub body when freewheeling

Thats the problem he is describing

A new spindle wont fix it, a bent spindle may have been the cause of the wear but now he needs to replace both freehub and spindle

 

[Vapin' Joe]

We could go on all night here, Zoiders. We might have to agree to differ. The freewheel will move when coasting as the hub will be oscilating on the spindle and the freewheel - whether screw on or freehub - has no choice but to oscilate with it.

A bent spindle will not damage a freewheel, only possible the bearings in the hub.

 

[MartinC]

This is totally normal. It's manufacturing tolerances in the freehub/freewheel bearings - it's why you only see it when the wheel's freewheeling. Legend has it that Bernard Hinault hated this and would get his mechanics to throw freewheels away until they found one that ran true enough for him.

 

[summerdays]

To say that this conversation is going above my head is not an exaggeration .. the wheel is only a month old, did it not come with a new spindle/freehub/QR? (I took the old wheel home with me cos I thought I might experiment with with the spokes/wheel trueing and I wanted to see exactly how thin the rims had got - the LBS probably thought I was completely mad and gave me every single bit they had replaced on the bike).

Let's make sure we are singing from the same hymnsheet here. I assume that what the OP means is oscillation of the sprockets rather than side-to-side play.

When in the stand, using the pedals to get the wheel spinning, then stopping turning the pedals, I noticed that the cassette oscillates closer and further away from the wheel by a millimetre or so. I haven't tried rocking the cassette by hand, but I have not noticed movement when trying to clean it.

 

[MartinC]

Sorry, I didn't explain very well.

The hub rotates on an axis defined by the spindle and it's bearings. When the drive is on (you're pedalling) the freehub/freewheel is locked to the hub and rotates with it around this same axis.

When the the wheel is still and the sprockets are rotating (freewheeling) the freehub/freewheel is rotating about an axis defined by it's own bearings not the wheel bearings.

In theory this axis is concentric with the wheel spindle. There are manufacturing tolerances in the bearing races and the threads cut on the hub and the freehub/freewheel to fix them together. This means that the hub axis and the freehub/freewheel axis may not be concentric - not parallel and/or not centred in the same place. The difference may be small but you'll see in movement (run out) between the sprockets and the adjacent spokes.

It's normal and expected. It will vary from hub to hub as the inaccuracies involved may add up or cancel each other out. It doesn't necessarily indicate any wear and it won't cause any transmission problems.

If any bearings are worn you'll feel the play in the cones or in the freewheel bearings by rocking the wheel or sprockets with your hand. If the spindle is bent the sprockets will run out of line but won't appear to wobble.

Sorry it's so complicated - hope I've helped.