help, chain falling off!

souter

Hi,
inspired by a recent thread here I decided to remove and clean my chain.
Several hours and multiple mishaps later I have a clean chain. But it's constantly falling off (falling off the big sprocket when starting in a high gear).
I'm a bit mystified as I'd cleaned it to prevent the (occasional) falling off and spit, now it's way worse.
A couple things I was thinking of:

1) I removed 3 links - messed up and got the wrong split link, then lost a rivet. But I stay in high gears so surely the tension will if anything be higher and catered for by the existing derailleur setup?
2) The chain isn't sitting right on the main sprocket.
3) The chain and gears are fairly old and poorly maintained. Could I have put the chain on backwards or something i.e. the chain and gears have worn down to a mutual understanding which I've reversed?

Any ideas?

Chips Lovell

Yes, get a new chain.

If its fairly old and you've already broke three links taking it off. Save yourself the hassle and get a new one.

RtD

I'd also suggest that the chain is jumping off because the deraileur is slightly out of position. This video might help.

blorg

You could also check the chain for a stiff link. I have one of these at the moment; somehow one of the links got gouged and the link will no longer rotate easily. This causes skipping in place in my case. You can check by running the pedals backwards and looking for when the derailleur skips (in my case the link is very stiff and clearly visible as a raised point on the otherwise flat chain.) You can feel it through a rag held around the chain if it is more subtle. These can apparently be massaged out in some cases although my one was too serious for this.

As el tonto says though you probably should get a new chain, although if the cassette and chainrings are well worn it could well skip worse than the old one did due to the lack of mutual understanding you refer to (I have personal experience of this with new chain on old cassette.)

cyclopath2001

souter wrote: »

But it's constantly falling off (falling off the big sprocket when starting in a high gear)

Are you using the left-most sprocket at the rear and the right-most chainwheel at the front?

If so, that could be causing the problem.

souter

and here's more information:

1)re: gear selection, I'm a grinder rather than a spinner, and even since consciously gearing down in preparation for right turns, the chain has been hopping off **way** more since my palliative efforts.
2) don't think there's any stiff link. That's the annoying thing - the chain looks and appears so shiny slinky, but won't mesh with the cogs.
3) wrt: deraileaur, I did a fair bit of manipulating the mechanism but the chain still looked detached from the sprocket irregardless of the tension applied by hand. The chain is not being stressed laterally.

I need to get this fixed asap, any suggestions for an old-skool 5 speed gear and chain combo +what specialist tools would I need? (forget the last bit - I can google too)

Freddy687

souter,
If you are a grinder you have definitely stretched the chain, so only the original position has a chance or working again.
If you really want to re-use the chain remember that not only can it be on backwards but also inside out.
This means there are 4 possible combinations, in your case with the gear being together so long only one of these is going to work.
Clean up a link and mark each side with a marker, "A" and "B".
If "A" is on the outside, then try the chain in the other direction. "A" is still visible, but upside down.
If no joy then turn the chain around to show "B". Repeat for both directions if needed.

If this does not work then you really need to look at new a chain and sprockets.

Mr. Presentable

Sounds like the chain went back on inside out.

souter

I flipped the chain around it worked on the first try. Nice. Definitely well worn and I'll look at getting a new drive train soon. Given I am an incorrigible grinder, is there anyone that supplies 5 speed rear cassettes - I did some preliminary research and can't believe that 7 appears to be the minimum cassette size now.

Bambaata

my chain fell off twice today at the waterford Duathlon grrrr!!!