Twisted and double looped chain

[hiker biker]

Afternoon (depending where you are)

Ok, so I got a flat on the rear wheel yesterday, so I took the wheel of and replaced the inner tube no problems at all, I put the wheel back on and I imagine it got caught on the chain and now its got twisted and got two loops on it, I have fiddled with it for hours now, my hands are black, and unfortunately I don't own a chain tool.

I need to get this fixed preferably for tomorrow as I have work.

I have included a picture thats the best I can currently provide.

any help guys?

[JohnV]

Interesting "twist of events", if I do say. I've seen this happen to others but have not encountered it myself. If you put some masking or painters tape on the seat tube below the front derailleur and mark the tape with a line designating the position of a part or mark on the derailleur, you should be able to move the derailleur up enough to clear the chainring so you can remove the chain. This will help you to untangle the chain a bit better than with the chain still on the chainring. When untangled, set the derailleur back to its original position by aligning the mark or part to the mark on the tape. Just make sure that the top of the tape is up against the derailleur or clamp so that you know what the original height of the derailleur was in reference to the chainring. You may have to make a slight adjustment if you don't get the derailleur back to its original position. Of course, if you can get a hold of a chain tool, that would be your best bet.

[hiker biker]

Thanks for the help John.

Well I didn't want to damage the chain in anyway or attempt to un-do without the correct tools. But I did however think "I wonder if I removed the rear derailer if I could then twist it round...?".

and I did and like magic the twist was out and both loops!

except... now I face another problem. whiclst I now have a perfectly straight chain its now not in the correct position in the derailer and I'm not sure how it should be.

[nameused]

(05-05-2011, 12:42 PM)hiker biker Wrote:  Thanks for the help John.

Well I didn't want to damage the chain in anyway or attempt to un-do without the correct tools. But I did however think "I wonder if I removed the rear derailer if I could then twist it round...?".

and I did and like magic the twist was out and both loops!

except... now I face another problem. whilst I now have a perfectly straight chain its now not in the correct position in the derailer and I'm not sure how it should be.

Seems to look right in the picture. Should have the chain feeding in through the top pulley then around in the cage down to the bottom pulley and headed out.
This picture might help:

[JohnV]

Not sure if this is what you mean, but the chain should be in the position shown on the shifters. Lets say you have a 21 speed bike and the left shifter at #3, chain goes on outer chainring. Right shifter on position 4, chain on fourth cog from the spokes. Then get on the bike, ride and shift. It should jump to the correct position if are off and the rear derailleur adjustments were not changed. If your chain path doesn't follow the photo that nameused posted, then do that first.

[cyclerUK]

(05-05-2011, 01:28 PM)nameused Wrote:  [
This picture might help:

I don't know if you have deliberately meant to show an error but the chain is wrong.
The chain should go directly from top jockey to lower one without going around any part of the cage. The chain should not touch any part of the cage at all.
(I presume there is a "pin" across behind the chain from front to rear cage plate. If so the chain would be very noisy when run.)

Study the chain route on this video:-
http://bikeride.com/install-rear-derailleur/

[hiker biker]

Hi guys

Thanks for all the help given.

I finally have the derailleur on correctly and the chain 100% straight and on properly.

Just got a few other problems to fix now and one being a pesky inner tube that I just put on. I pumped it up before putting it on the tyre and it was all good then once I put it in the tyre its not pumping up? so I took it out to try again and it pumps up full? I seriously don't understand whats going on with it.

Just need to sort my gears out now too.

Thanks again.

[nameused]

(05-05-2011, 02:36 PM)cyclerUK Wrote:  

(05-05-2011, 01:28 PM)nameused Wrote:  [
This picture might help:

I don't know if you have deliberately meant to show an error but the chain is wrong.
The chain should go directly from top jockey to lower one without going around any part of the cage. The chain should not touch any part of the cage at all.
(I presume there is a "pin" across behind the chain from front to rear cage plate. If so the chain would be very noisy when run.)

Study the chain route on this video:-
http://bikeride.com/install-rear-derailleur/

Yeah I noticed that, but it was the best looking picture that generally showed how the chain should go through. I thought it looked a little weird, so I read the rest of the thread and it was about that problem.

[hiker biker]

So I just rode my bike, tried changing gears and BAM! the wheely part of the derailleur has completely snapped off and the whole derailleur seems a bit warped.

I think I may just be wasting my time and money on this bike and might just invest in a decent bike...

---

So I just rode my bike, tried changing gears and BAM! the wheely part of the derailleur has completely snapped off and the whole derailleur seems a bit warped.

I think I may just be wasting my time and money on this bike and might just invest in a decent bike...

[speedkar9]

Maybe it got caught in a spoke when it was in the larger sprockets. Same happened to me .

Check your rim for any spoke damage.

[hiker biker]

(05-09-2011, 10:41 AM)speedkar9 Wrote:  Maybe it got caught in a spoke when it was in the larger sprockets. Same happened to me .

Check your rim for any spoke damage.

Yup its damaged, this happened right after I fixed it too. well I didn't actualy buy this bike, its my brothers and tis been stashed in his garden for months so is rusty and pretty much knackered.
I just attempted to bring it back to life... and clearly failed.

I think I may just buy a new bike of my own and use my knowledge from this site to keep it well maintaned

[cobra@55]

I've had this problem a few times and there was always two loops. The way to get them out is to "roll" the loops towards each other and when they meet both loops will disappear. What i mean by rolling is to push up on side of the loop and pull down on the other. This will move the loop along the chain until it meets the other loop......works every time.

---

I've had this problem a few times and there was always two loops. The way to get them out is to "roll" the loops towards each other and when they meet both loops will disappear. What i mean by rolling is to push up on side of the loop and pull down on the other. This will move the loop along the chain until it meets the other loop......works every time.

[cny-man]

(05-08-2011, 02:28 PM)hiker biker Wrote:  So I just rode my bike, tried changing gears and BAM! the wheely part of the derailleur has completely snapped off and the whole derailleur seems a bit warped.

I think I may just be wasting my time and money on this bike and might just invest in a decent bike...

---

It's not the bike that's wasting your time, it's your haphazard approach. There's no need to remove the derailleur when working on a rear wheel. You not only removed it but then rotated it before remounting, causing the chain loops. The BAM was likely caused by incorrectly mounting the derailleur or routing the chain wrong.

I would suggest you find a bike co-op or more knowledgeable friend to assist before you do more damage.