Snagged chain - Help

[2WheelsNot4]

Managed to get the leg of the waterproofs caught in the chainring, which in turn threw the chain which has now become jammed between the frame/motor and inner edge of the chainring and try as i might I cant get to to come back out that slot. I think the space between is just too narrow and while it went in, I reckon thats only because it was under pressure.

I cant remove the crank and then arm as I havent those tools. Might be able to split the chain, but theres no movement in it back and forth so im not sure thats going to do much(Though only option at this stage is to try.

So if it comes down to it, what crank puller do I need ?. The one i have(standard shimano) wont work because the 'push' bit is too thin and just goes into the hollow space of the axle, and it doesnt appear long enough anyway, and what tool is for the chainring lockring ?.
I'm aware at a push i could hammer the lockring off using a screwdriver to tap it round, only that always causes damage, not critical damage, more cosmetic, but I dont want to go that route and would prefer the proper tool.

What an almighty fucking pain in the arse.

I actually had to cut free the leg of the waterproofs at the bottom it was wrapped that tightly to my leg and was beginning to cut off the circulation. Thank god for pocket knives.

 

[Zimmerframe]

I had a phase of my Shimano bike losing the chain off the chainring regularly (crap mech) Jammed in there impossibly a few times, can't remember how but always got it out in the end -I think levering off the chainring or spider and then moving the cranks back or forwards - always managed to do it on the trail so didn't have anything too fancy with me. Make sure the clutch is off and back wheel off the ground - gives you more chain to play with - and potentially using the wheel to pull the chain back depending how you lever the chain at the crank end. Might have used plastic tyre levers or something - really don't recall.

Cranks should come off easily - loosen the two pinch bolts, lift the silly little plastic safety lock wedge up between them then remove the cap (anticlockwise - shouldn't be that tight) and they should slide straight off. Keep an eye on the caps winding themselves off after you put them back on when you ride it.

I did have the lockring removal tool later on, but gave it away. Managed to get it off once without it - though it wasn't easy and took some ingenuity. CLOCKWISE to remove !!!

EDIT : was a dumbo and thought he meant a Shimano motor so above is for that - not Bosch.

 

[Mikerb]

Things to try ..........
The chainring is strong but there is some flex and you only need 1mm so a strong screwdriver to act as lever...........the chain needs to be released upwards, so whilst applying a little leverage on the chainring you also need another lever to push the chain upwards..............that may be easier if you have a friend to help. If the chain still will not move it is likely jammed up against a part of the chainring or frame that is protruding. Try using some grease or thick oil and whilst applying a bit of leverage see if you can get a feeler guage between the chain and that protruding part..............then revert to the original leveraging method.

 

[steve_sordy]

.....Try using some grease or thick oil and whilst applying a bit of leverage see if you can get a feeler guage between the chain and that protruding part..............then revert to the original leveraging method.

To use the feeler gauge as a ramp, if it wasn't clear enough.
Or any piece of really thin metal, like that cut from a can.

Whenever I have had the chain stuck like that (about three times, years ago), I just grabbed a handful of chain and pulled it upwards and away. It always, always, left small gouges in the alloy frame. It never happened on the same bike twice, because I always made adjustments to the bike afterwards. ie I found the cause and fixed it.

 

[2WheelsNot4]

Sorted it with my trusty Estwing hammer and a long screwdriver

Just really a case of bashing it back out. Small taps on the hammer against the links that were stuck and it finally came free, and THANK FUCK

Is there nothing a good hammer can't achieve

I'll take note of whats been said. Ring was looking a bit jaggy, so I'll have to replace that sooner rather than later.
Cheers for the suggestions.

 

[2WheelsNot4]

CLOCKWISE to remove !!!

Duly noted. Though it is a bosch motor, though i guess it will be the same. Theres usually a bit of thread showing you can work out direction from
I would also refer to manual/yt for instructions.

 

[Zimmerframe]

Duly noted. Though it is a bosch motor, though i guess it will be the same. Theres usually a bit of thread showing you can work out direction from
I would also refer to manual/yt for instructions.

Ooops .. sorry .. I read the Shimano comment and thought you had a Shimano setup, but not the e8000 lock ring tool .. doh !

Glad you got it out anyway.

 

[Stihldog]

I actually had to cut free the leg of the waterproofs…

Thank gawd you had a knife. Having to walk home with no pants on could take this to a whole other level.

Similar thing happened to me earlier this year. Suspiciously I was wearing waterproof pants also. Bosch motor and ethirteen chainring. The cuff of my pants went past the guard and into the chaining. I was stuck …but still coasting.

I panicked and made another cadence revolution. The chain wedged itself between the frame and chainring as it came off the cogs. Half of the little chain guard went flying behind me.

When I finally stopped I gave the chain a little tugg and freed it from pinching itself between the chainring and frame. Fortunately I was able to replace the chain and gather the guard part.


The small screw hole was stripped on the guard but I just inserted a thin piece of soft wood into the hole. Embarrassing moment averted.

 

[2WheelsNot4]

Thank gawd you had a knife. Having to walk home with no pants on could take this to a whole other level.

Similar thing happened to me earlier this year. Suspiciously I was wearing waterproof pants also. Bosch motor and ethirteen chainring. The cuff of my pants went past the guard and into the chaining. I was stuck …but still coasting.

I panicked and made another cadence revolution. The chain wedged itself between the frame and chainring as it came off the cogs. Half of the little chain guard went flying behind me.

When I finally stopped I gave the chain a little tugg and freed it from pinching itself between the chainring and frame. Fortunately I was able to replace the chain and gather the guard part.

View attachment 131803
The small screw hole was stripped on the guard but I just inserted a thin piece of soft wood into the hole. Embarrassing moment averted.

Pretty much identical. You can walk the bike back if its not too difficult and stuck fast as mine was with the added complication of the crank arm and pedal jammed tight against my leg. Walking it backwards means the chainring turns back and that can free the cloth from between the ring and the chain. Outside of that fix its cutting time and there goes another set of trousers.

 

[Mikerb]

others can correct me if I am wrong but as far as I understand it the Bosch chainring nut is reverse thread.....clockwise to undo it, whereas the Brose is standard thread.....anti clockwise to undo it. D ont know about Shimano or Yamaha etc.

 

[Mr President]

Happened to me once, but could get the chain out by loading the suspension. It get’s jammed in when you’re sat on the bike and you can’t get it out when you’re off the bike.

 

[Stihldog]

others can correct me if I am wrong but as far as I understand it the Bosch chainring nut is reverse thread.....clockwise to undo it, whereas the Brose is standard thread.....anti clockwise to undo it. D ont know about Shimano or Yamaha etc.

You’re right about the Bosch chainring nut. Left hand thread. I believe that the castle nut is aluminum. Probably so those fine threads will strip before the crank threads.

A spare castle nut is a good idea …and fairly cheap.

 

[Mikerb]

You’re right about the Bosch chainring nut. Left hand thread. I believe that the castle nut is aluminum. Probably so those fine threads will strip before the crank threads.

A spare castle nut is a good idea …and fairly cheap.

ta!.....in terms of my knowledge of fasteners I believe the reason it is ally is so that it can achieve larger thread friction despite having very few threads....at a medium torque. It is for that reason that I believe it is a single use nut with the threads actually stretched on first torque up and therefore unable to achieve the same thread friction a second time. If I change a spider of chainring I always use a new castle nut...........usually about £9 including the rubber ring.

 

[steve_sordy]

@2WheelsNot4 Why were you riding with baggy trousers at the ankle? I ruined several pairs of trousers and had one unplanned dismount because I failed to deal with the bagginess. All many years ago, when I was new to biking in long trousers.

 

[Stihldog]

Which is why I stopped riding with bellbottom-flared-pant.
I don’t miss the 70’s.

 

[Jackware]

Buy these - just make sure they're the ebike versions.

 

[Mikerb]

Which is why I stopped riding with bellbottom-flared-pant.
I don’t miss the 70’s.

Bell bottoms were OK..............based on sailors pants and therefore easily able to fold the bottoms up to the thigh for scrubbing the desks...................or for avoiding getting them stuck in a bicycle chain

 

[CaptKirk]

Sorted it with my trusty Estwing hammer and a long screwdriver

Just really a case of bashing it back out. Small taps on the hammer against the links that were stuck and it finally came free, and THANK FUCK

Is there nothing a good hammer can't achieve

I'll take note of whats been said. Ring was looking a bit jaggy, so I'll have to replace that sooner rather than later.
Cheers for the suggestions.

Best bet here is to help yourself and buy/borrow the correct tools to do the job. Nothing worse than trying to take a shortcut and then spending twice as much time and money because you cracked or scratch the frame(Carbon)

 

[Zimmerframe]

fold the bottoms up to the thigh for scrubbing the desks

White Collar Sailors ?

 

[Mikerb]

White Collar Sailors ?

seamen...think I spelt that right?

 

[steve_sordy]

Yey to all Captain Pugwash enthusiasts!!

Seaman Stains?
Master Bates?
Roger the cabin boy?