Another Slipping Chain

[JtB]

The chain on my son's bike keeps slipping on the small rear sprocket (irrespective of which front gear is selected).

The condition of the chain is good (i.e. well lubricated, no stretch whatsoever and no damaged links).

I've included some photos below of the sprockets (front and rear) and rear gear selector.

Anyone got any ideas?

 

[yashicamat]

Maybe it's the photograph perspective, but in the last photograph it looks like the rear mech isn't in line with the cassette? We appear to be looking directly at the mech, but the cassette is at an angle . . .

Perhaps the mech has had a bash from the outside and it's knocked it out of alignment a bit?

Rob

 

[JtB]

The rear gear change has definitely taken quite a few bashes.

 

[JtB]

Does the misalignment of the rear gear selector look sufficient to cause the chain to slip?

Will have to try twisting it back into alignment.

 

[bad boy]

Maybe it's the photograph perspective, but in the last photograph it looks like the rear mech isn't in line with the cassette? We appear to be looking directly at the mech, but the cassette is at an angle . . .

Perhaps the mech has had a bash from the outside and it's knocked it out of alignment a bit?

Rob

Spot on looks like the rear hanger is bent to me that could cause a bad chain line and hence the noise.

When you say the chain is well lubricated can I ask what your using on it ?, and also have you properly cleaned it or just chucking stuff on it every so often ?.

 

[JtB]

Its more than just noise, it slips very easily as soon as you apply force on the peddles.

To lubricate the chain I use engine oil.

For some reason, both my sons have difficulty staying on their bikes for more than a few rides without falling off and so both their bikes tend to take quite a bashing.

 

[bad boy]

If its slipping then its either the chain or the cassette sprocket in your case as its only happening on the rear small.

I cant really see from the pic but have a look on line for cassette wear and it will give you a picture of what a worn cassette looks like which is described as being a sort of shark fin shape.

 

[shumidrives]

it could be the cassette is worn as when you look at the smallest sprocket the teeth dont line up with all the rest indicating that it has moved

 

[Ivan Ardon]

Does the misalignment of the rear gear selector look sufficient to cause the chain to slip?

Will have to try twisting it back into alignment.

Yes, it does. It's very bent.

You've got an aluminium hanger, it could well snap when you try bending it back. It could be worth locating a spare just in case (and they're stupidly expensive for what they are).