Bike Chain Keeps Popping Off, WHY?!
04-26-24, 02:30 PM
#1
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Bike Chain Keeps Popping Off, WHY?!
The chain on my bike likes to pop off randomly when I'm riding. It's a bit of an issue as I use my bike to get between work and classes and it takes me a bit to get it back on. How do I stop this from happening?
04-26-24, 02:51 PM
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Sorry, there are myriad reasons for a chain popping off. I don't know how anyone can solve this without looking at the bike, or not even knowing what kind of bike it is, or at least getting a better description than "randomly." Take it to a bike shop. A good mechanic should be able to diagnose the cause in minutes, and if your bike needs new parts like a chain or cogs, there's no getting around it. Spend a little money or learn a little about how a bicycle works.
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04-26-24, 03:22 PM
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One likely cause is a bent chainring tooth, but that's only one of many possibilities.
We'd need to know much more before being able to offer an intelligent response. Then again, even an excellent description isn't close to actually eyeballing the bike.
If there's a local bike co-op go there, otherwise go to a bike shop, or if you're mechanically inclined, reader watch lots of tutorials on the net.
We'd need to know much more before being able to offer an intelligent response. Then again, even an excellent description isn't close to actually eyeballing the bike.
If there's a local bike co-op go there, otherwise go to a bike shop, or if you're mechanically inclined, reader watch lots of tutorials on the net.
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04-26-24, 04:19 PM
#6
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Okay, let me describe the situation a bit better. I've noticed that my chain likes to pop off after hitting a bump, but it's not every single time. I'll look and see if any of the chain-ring teeth are bent and find out how to fix it. I would like to avoid spending money to fix something, especially if it's a simple fix, as I am a college student (please keep this in mind)
04-26-24, 04:24 PM
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might have too much chain slack
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04-26-24, 04:39 PM
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04-26-24, 04:42 PM
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This ^^^
As others have also noted, it could be a combination of things, including bent chainring or cog teeth, but the fact that it's related to going over a bump makes chain tension a most likely culprit. On a beach cruiser type bike, adjusting chain tension would require loosening the nuts that hold the rear wheel in the frame, sliding the wheel back, and re-tightening the nuts. There is a balance between too loose and too tight for chain tension. Too tight will make pedaling more difficult. For someone with experience working on bikes, this is pretty elementary. For someone without experience, it might take some trial and error to get it right. Also, make sure the wheel stays centered in the frame.
As others have also noted, it could be a combination of things, including bent chainring or cog teeth, but the fact that it's related to going over a bump makes chain tension a most likely culprit. On a beach cruiser type bike, adjusting chain tension would require loosening the nuts that hold the rear wheel in the frame, sliding the wheel back, and re-tightening the nuts. There is a balance between too loose and too tight for chain tension. Too tight will make pedaling more difficult. For someone with experience working on bikes, this is pretty elementary. For someone without experience, it might take some trial and error to get it right. Also, make sure the wheel stays centered in the frame.
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04-26-24, 05:01 PM
#10
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This ^^^
As others have also noted, it could be a combination of things, including bent chainring or cog teeth, but the fact that it's related to going over a bump makes chain tension a most likely culprit. On a beach cruiser type bike, adjusting chain tension would require loosening the nuts that hold the rear wheel in the frame, sliding the wheel back, and re-tightening the nuts. There is a balance between too loose and too tight for chain tension. Too tight will make pedaling more difficult. For someone with experience working on bikes, this is pretty elementary. For someone without experience, it might take some trial and error to get it right. Also, make sure the wheel stays centered in the frame.
As others have also noted, it could be a combination of things, including bent chainring or cog teeth, but the fact that it's related to going over a bump makes chain tension a most likely culprit. On a beach cruiser type bike, adjusting chain tension would require loosening the nuts that hold the rear wheel in the frame, sliding the wheel back, and re-tightening the nuts. There is a balance between too loose and too tight for chain tension. Too tight will make pedaling more difficult. For someone with experience working on bikes, this is pretty elementary. For someone without experience, it might take some trial and error to get it right. Also, make sure the wheel stays centered in the frame.
IF you can prop up the rear wheel and spin the pedals-
Slowly turn them and observe the amount of "sag" in the chain after 8-10 revolutions.
IF the chain ring & cog are centered, the sag should remain consistent.
IF it tightens up, something is off center and they adjusted to not get over tight which can damage parts if too severe.
So, before sliding the wheel back, do a quick check to prevent an over tight condition on the chain.
Huffys tend to have lower quality parts and store assembly.
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04-26-24, 05:34 PM
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Assuming Mr. 66 is psychic and you truly have single speed bike, ie. one with a coaster brake, then I'm with the others in suspecting a slack chain.
This is easily fixed, by loosening the rear wheel and sliding it back.
Just be aware of 2 concerns as you do this.
1- you must hold the wheel centered between the chainstays (front of wheel, behind pedals)
2- DO NOT pull out all the slack. The chain needs some slack to work right. Snug the wheel and push the lower loop up and down in the middle. It needs about 1/4" or so. Then check it's centered & tighten the wheel nuts completely.
You can also search tutorials for installing a coaster brake wheel.
This is easily fixed, by loosening the rear wheel and sliding it back.
Just be aware of 2 concerns as you do this.
1- you must hold the wheel centered between the chainstays (front of wheel, behind pedals)
2- DO NOT pull out all the slack. The chain needs some slack to work right. Snug the wheel and push the lower loop up and down in the middle. It needs about 1/4" or so. Then check it's centered & tighten the wheel nuts completely.
You can also search tutorials for installing a coaster brake wheel.
Last edited by FBinNY; 04-28-24 at 01:48 PM.
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04-26-24, 07:03 PM
#12
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Recently worked on a bike who's owner had a similar complaint, the chain would keep coming off. The plastic spoke protector (dork disk) was broken and was binding between the spokes and the cassette, causing the cassette to continue spinning even when coasting...this caused the top run of the chain to push forward and slacken, add even a slight bump in the road and whallah, the chain pops of the single ring crankset...removal/replacement of the spoke protector solved the issue.
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Last edited by Zef; 04-26-24 at 07:12 PM.
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04-26-24, 07:10 PM
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04-26-24, 07:29 PM
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Generally single speed bikes use a dropout that allows the wheel to be moved forward or back to adjust chain slack...when chain slack is minor of course...if the chain is too long then it has to be shortened to the correct length then slide the wheel in the dropout to remove the slack...but not too tight...but just right.
It could be a bent chain ring or a few other things...without decent info and a picture it is impossible to give decent advice or suggestions...but it is what it is...perhaps take Uber???
It could be a bent chain ring or a few other things...without decent info and a picture it is impossible to give decent advice or suggestions...but it is what it is...perhaps take Uber???
04-26-24, 07:43 PM
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Generally single speed bikes use a dropout that allows the wheel to be moved forward or back to adjust chain slack...when chain slack is minor of course...if the chain is too long then it has to be shortened to the correct length then slide the wheel in the dropout to remove the slack...but not too tight...but just right.
It could be a bent chain ring or a few other things...without decent info and a picture it is impossible to give decent advice or suggestions...but it is what it is...perhaps take Uber???
It could be a bent chain ring or a few other things...without decent info and a picture it is impossible to give decent advice or suggestions...but it is what it is...perhaps take Uber???
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04-26-24, 08:36 PM
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04-27-24, 06:29 AM
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This ^^^
As others have also noted, it could be a combination of things, including bent chainring or cog teeth, but the fact that it's related to going over a bump makes chain tension a most likely culprit. On a beach cruiser type bike, adjusting chain tension would require loosening the nuts that hold the rear wheel in the frame, sliding the wheel back, and re-tightening the nuts. There is a balance between too loose and too tight for chain tension. Too tight will make pedaling more difficult. For someone with experience working on bikes, this is pretty elementary. For someone without experience, it might take some trial and error to get it right. Also, make sure the wheel stays centered in the frame.
As others have also noted, it could be a combination of things, including bent chainring or cog teeth, but the fact that it's related to going over a bump makes chain tension a most likely culprit. On a beach cruiser type bike, adjusting chain tension would require loosening the nuts that hold the rear wheel in the frame, sliding the wheel back, and re-tightening the nuts. There is a balance between too loose and too tight for chain tension. Too tight will make pedaling more difficult. For someone with experience working on bikes, this is pretty elementary. For someone without experience, it might take some trial and error to get it right. Also, make sure the wheel stays centered in the frame.
I was able to reposition the back wheel and reduce the slack. I haven't taken it for a spin to test it out (I need to give myself some break from a week of riding) but I'll give an update of the chain-popping troubles on Monday!
Thank y'all for all the advice, it's been really helpful.
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04-29-24, 01:58 PM
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After a day of riding to and from work and campus, I can say with some amount of certainty that my bike chain is good! It did seem that the chain was just too loose, and I'm just disappointed in myself for not noticing it before. It probably happened when I was changing the inner tube a while back and didn't tighten the bolts well enough, allowing for the back tire to move out of place at some point before I retightened them.
Once again, thank you all for the advice!!!
Once again, thank you all for the advice!!!
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04-29-24, 02:00 PM
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After a day of riding to and from work and campus, I can say with some amount of certainty that my bike chain is good! It did seem that the chain was just too loose, and I'm just disappointed in myself for not noticing it before. It probably happened when I was changing the inner tube a while back and didn't tighten the bolts well enough, allowing for the back tire to move out of place at some point before I retightened them.
Once again, thank you all for the advice!!!
Once again, thank you all for the advice!!!
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04-30-24, 06:16 AM
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Assuming Mr. 66 is psychic and you truly have single speed bike, ie. one with a coaster brake, then I'm with the others in suspecting a slack chain.
This is easily fixed, by loosening the rear wheel and sliding it back.
Just be aware of 2 concerns as you do this.
1- you must hold the wheel centered between the chainstays (front of wheel, behind pedals)
2- DO NOT pull out all the slack. The chain needs some slack to work right. Snug the wheel and push the lower loop up and down in the middle. It needs about 1/4" or so. Then check it's centered & tighten the wheel nuts completely.
You can also search tutorials for installing a coaster brake wheel.
This is easily fixed, by loosening the rear wheel and sliding it back.
Just be aware of 2 concerns as you do this.
1- you must hold the wheel centered between the chainstays (front of wheel, behind pedals)
2- DO NOT pull out all the slack. The chain needs some slack to work right. Snug the wheel and push the lower loop up and down in the middle. It needs about 1/4" or so. Then check it's centered & tighten the wheel nuts completely.
You can also search tutorials for installing a coaster brake wheel.
04-30-24, 09:05 AM
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All my IGH chains go slack/ tight. Too slack and they smack my chain cases.
The only way to get it perfect is to turn the chain until you find the tight spot and then set that with the least slack you can. Keep testing it till it's all good. And it only takes about 1/64" difference in the axle position to go from tight to too loose.
Even without a cover, the least slackness is best.
And don't neglect chain cleaning.
My last bike I was switching from Nexus 7 to SA 5w. I thought the chain line was good but was off 1/8" and kicked it off. Had to get a 11mm longer BB.
The only way to get it perfect is to turn the chain until you find the tight spot and then set that with the least slack you can. Keep testing it till it's all good. And it only takes about 1/64" difference in the axle position to go from tight to too loose.
Even without a cover, the least slackness is best.
And don't neglect chain cleaning.
My last bike I was switching from Nexus 7 to SA 5w. I thought the chain line was good but was off 1/8" and kicked it off. Had to get a 11mm longer BB.
Last edited by GamblerGORD53; 04-30-24 at 09:09 AM.
04-30-24, 09:38 AM
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Slack chains on coaster brake bikes as very common. Add to that the fact that she was able to work the chain back on.
So, while there were other possibilities, it made sense to start with the likeliest before looking for the zebras.
As it turned out, that's what it was.
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Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
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