Chain Dropping

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aidso
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Chain Dropping

Postby aidso » Tue Nov 13, 2012 14:32 pm

I had a wee search and most people seem to have the problem when they are shifting, but I am getting chain slippage when standing up and powering up a climb. I will be in the largest of 3 cogs and the chain will snap forward and drop into the middle - sometimes sending me into a face-plant over the bars.

As far as I can tell, the shift is happening smoothly and it stays in position when pedalling along, its only when I stand and apply pressure. The teeth on the front derailler appear to be sharpish and aren't flat.

Any other ideas?

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The Rookie
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Re: Chain Dropping

Postby The Rookie » Tue Nov 13, 2012 14:45 pm

Badly indexed front mech, with the mech in the right place the chain shouldn't be able to come off the big ring!

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cooldad
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Re: Chain Dropping

Postby cooldad » Tue Nov 13, 2012 14:45 pm

Something is worn or not adjusted properly.
But I really hope your front derailleur doesn't have teeth.
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aidso
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Re: Chain Dropping

Postby aidso » Tue Nov 13, 2012 15:26 pm

Should the teeth be flat/squared?

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cooldad
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Re: Chain Dropping

Postby cooldad » Tue Nov 13, 2012 16:19 pm

Front derailleurs don't have teeth.
Do you mean chainrings?
I don't do smileys.

There is no secret ingredient - Kung Fu Panda

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aidso
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Re: Chain Dropping

Postby aidso » Tue Nov 13, 2012 16:34 pm

sorry haha, yes I mean the chain rings.

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bennett_346
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Re: Chain Dropping

Postby bennett_346 » Tue Nov 13, 2012 18:28 pm

Too low a gear in the back i bet. Why are you climbing in the largest of 3 chainrings? I guarantee its that not a setup issue.

LJ.
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Re: Chain Dropping

Postby LJ. » Tue Nov 13, 2012 19:42 pm

High screw on the front derailleur maybe to move it further out?

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aidso
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Re: Chain Dropping

Postby aidso » Tue Nov 13, 2012 20:01 pm

I'll try the screw adjustment - looking down I thought there was enough clearance etc but I'll give it a go.

And why not climb in the highest ring? Gears are there to be used.

Dirtydog11
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Re: Chain Dropping

Postby Dirtydog11 » Tue Nov 13, 2012 20:23 pm

aidso wrote:I'll try the screw adjustment - looking down I thought there was enough clearance etc but I'll give it a go.

And why not climb in the highest ring? Gears are there to be used.


Because your chainline would be better (more direct) if you where in the middle or granny .

Sound like you?

http://www.intownbicycles.com/how-to/ar ... cles-gears

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aidso
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Re: Chain Dropping

Postby aidso » Tue Nov 13, 2012 20:40 pm

Dirtydog11 wrote:
aidso wrote:I'll try the screw adjustment - looking down I thought there was enough clearance etc but I'll give it a go.

And why not climb in the highest ring? Gears are there to be used.


Because your chainline would be better (more direct) if you where in the middle or granny .

Sound like you?

http://www.intownbicycles.com/how-to/ar ... cles-gears


Quite possibly. I shall pay attention to the back next time it happens as it could be, in too low a gear. I don't have the same problem when I'm racing so didn't think it was a technique. Cheers


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