Chain Slip - Chain Slipping Over Cassette

I'm having a problem with the chain slipping over the cassette so I decided to record it and slow things down to have a closer look.
Updated April 2021 I changed my cassette and the slipping went completely away. I used an ORDRO head cam taped onto the seatstay to film the problem.

[@luvtheceltics]

Had the same issue after replacing new chain and new cassette on a 10 speed rear. Specifically the chain was bouncing between the 10th (hardest) and 9th cogs. Ended up being my rear derailleur was slightly bent that I must have knocked when taking the rear wheel off. Anyhow went to the LBS and the mechanic said within 5 secs just eyeballing my RD it would be the problem, and so it was. I guess like a lot of guys on this thread you think you know how to fix most things, and it’s times like these that bring you back to reality 😎

[@iforgotilikebikes8543]

I hear you. I made sure my chain line and RD were as straight as humanly possible with my eyes long before this problem happened. I knew about it, but the RD seemed fine. Luckily, someone else's comment worked for me! This journey is all about learning through screwing up and breaking stuff, for me, that is.

[@mumenrider5696]

It's usually caused by a new chain on a badly worn cassette (even moderately worn cassette can cause problems)/new cassette on a worn chain. Mixing new and worn drivetrain components do not go along well. The chain and the cog do not fit when one is worn, and when you pedal hard, the chain tends to go over the top of the cassette teeth, slips, and falls on the next valley of the cassette, and the cycle repeats...the solution for that is to replace the worn part with a new one...

[@unixfreak]

Having this issue since last week, one of the spokes broke off of my rear wheel, so i ordered a replacement wheel (came with a pre-installed shimano cassette), and the chain slips every few links it seems, virtually unrideable. Just saw your comment, and i'm going to try a new chain, hoping this fixes it!

[@johnrefe]

I have new chain, new cassette and it slips like a sh* ...

[@mumenrider5696]

@@johnrefecheck that the rear derailleur is not bent or misaligned, and the chainrings upfront are not worn out..also check that the derailleur jockey wheels are not worn out as well ..

[@unixfreak]

I ended up getting a shimano hyperglide chain, and it works perfectly. I'm assuming my old chain was stretched from use, and just didn't want to connect properly with the new cassette 👍 works fine now, yay.

[@iforgotilikebikes8543]

Yeah, man! Replacing both together totally worked for me. I should have done that first but was playing the "why replace it because it looks fine" angle, which failed. lol

[@tolitsdterrible4785]

Based on my experience, if the chain is new, the most common cause is chain with stiff link. You can easily find the stiff link when you reverse the pedaling direction. Just loosen the stiff link. Another is worn out cog.

[@alo0ann]

I bought a new chain and it's causing it. How do I fix it.

[@tolitsdterrible4785]

@@alo0ann If you find the stiff link, lubricate it, try to bend it sideways, both directions and work it and repeat as necessary. If that doesn't work, you can use a right size flat head screwdriver. Place the head between the plates and twist it to open it up a bit.

[@kristoffercarlosguerra6946]

you would want your rear derailleur to be angled so that the chain ends up hugging the cassette more, as it should.

[@oinkooink]

My new 5 month old bike skips on the smallest cog? Judging by many of the comments here...stiff chain link or something? I haven't lubed the chain since I bought it. EDIT: Issue seems for me that several chain links had gone stiff. I hadn't oiled the chain since purchase 5 months ago. There were minor rust sections and raised links you could see from sideways. It was slipping mainly on the smallest cog I suppose because the smallest cog has the least surface area so when those seized and raised chain links went around it they just did not fit snug, whereas on the larger cogs with more surface area that wasn't so much a problem. I figured this out and fixed it myself before I had to go cap in hand to the bike shop. So...oil your chain kids.

[@iforgotilikebikes8543]

Awesome to know! Hopefully that will help some others without RD or cassette problems. Thanks a ton. I waxed my chain and have been loving it.

[@dennisespinosa4115]

I had the same problem until now..how do i fix it,,it slips on smallest cog only

[@XxNoMercyNL]

New casette sadly

[@surendharm3566]

I too have the same problem. Even after changing the crankset, chain and cassette, it is not cleared

[@lesterjohnescanlar5446]

@@surendharm3566 im having the same issue. Im using a brand new shimano groupset. The issue had been there already and i thought changing everything would fix it but even with compatible chains cassette and crank, it still slips in the smallest and the next one

[@iforgotilikebikes8543]

@@surendharm3566 Check your RD, hopefully you did by now! lol.

[@rickdeckard9810]

I have the exact same problem and manufacturer wants a similar video. Did you record that on a Gopro, how did you mount? thanks a lot.

[@ayshathanjala5131]

It's your chain problem

[@iforgotilikebikes8543]

Sorry to hear that. I used my head camera which is a ORDRO head cam with a wide-angle lens.

[@mark-on-zwift]

I have this exact issue as well. I have a brand new chain ( KNC generic ) and Shimano Ultegra components Tried new casette - same issue. Tried new casette, different wheel - same Issue Fiddled with B-screw - same issue Shifting is crisp and clean and indexed correctly. It does not change gear, it literally just seems to pull over the sprocket under load. It's the most frustrating problem ever. Given the process of elimination above I can assume only 2 issues. Either the frame is flexing to a point where alignment is an issue ( doubt it, Trek Madone 5.2 - bulletproof ) or the rear derailleur is misaligned / bent / not wrapping around enough ( weak spring ) Gonna investigate the latter and will give feedback

[@iforgotilikebikes8543]

That's super annoying! How's your chainline looking? Definitely check your angles of your derailleur. Hopefully you figured it out by now. Sorry for the late reply.

[@fahadiqbal6019]

Hey, did you find out what was causing the issue? I just changed my chain and the chain slips in the bottom 2 cogs under load

[@mark-on-zwift]

@@fahadiqbal6019 - I fixed it by replacing my chainrings. Turns out they were totally worn. Only noticed it when comparing to the new one, but now its like a new bike. I had to get a tiagra 10spd double 53/36 because A. Its a 10spd and B. Shimano has absolutely no stock in SA since covid. But its looks great and works even better! And was less than half the price of ultegra!

[@mellow2879]

Could be that chain is too long you need to shorten it

[@taichihead42]

Did you fix the problem????

[@latteti8627]

I have save problem in my 3 small cogs slipping Any suggestion sir even if I change my chain still slipping

[@YacineBenabid128]

you have a worn cassette you need a new one

[@mellow2879]

Did you try shortening the chain?

[@baggies5000]

@@mellow2879 I had this problem after replacing the chain.I took chain off and compared it to old one and found new chain was three full links longer.I removed them and problem solved.Thanks.

[@MiaMia-px5xo]

No, even with a new cassette there is this problem!!@@YacineBenabid128

[@cristianvargas2191]

I‘ve the same problem. Originally my bike was a 3x9 Slx transmission and it slip gears. I converted to a 1x9 using the same cranks, new cassette, new chain, new chainring and it still slips gears in the smallest cogs. I’ve checked the chain line and put washers to correct the angle since the cranks are not designed to work in a one-by setup, and it looks fairly ok. I don't have any idea what is happening, since the original configuration happened either. Can anyone give any advice of how to solve it pls 😭

[@user-xu4qk3cy6u]

Maybe the chain is not compatible in the cassette try to move it little by little the chain check if it's sliding then you know it's not compatible...

[@keygos8834]

It looks like one of the teeth on the smallest cog is partly damaged ( 2:56), and your entire cassette looks worn down. Pretty sure, it is the problem. New cassette and new chain would solve it.

[@iforgotilikebikes8543]

It did! Thanks for the comment! Comments like yours worked for me!

[@thristianarceno9400]

Same problem . After i replace my chain . Its slip on a high gear when im riding . Any recommendation ?

[@am10231]

How did you fix it ?

[@RxT7A]

I have the same problem as well. It always slips when I switch it to the highest gear. Did you get your bike fixed yet?

[@idbhai]

I have the same problem... It happened after I put on a new chain..Did you find any fix for this?

[@iforgotilikebikes8543]

Absolutely. I needed a new cassette so I bought one and no more slipping at all. I think the slight wear on the cassette is the culprit even if you don't notice any by eye. Try installing a new cassette and let me know how it worked out for ya.

[@iforgotilikebikes8543]

@Jack Ophelott Make sure your chainline is as straight as possible. My chain was slipping as I was pedaling backwards until I moved my BB over a bit to the right and the chainline was perfect which solved my problem. Hopefully you figure it out.

[@praveenkumar-ib2oj]

Same problem pls help me

[@user-ub2cg5hu8x]

Thats happening to me

[@iforgotilikebikes8543]

Replace the cassette and chain together. That's all I did to fix it.

[@KuyaGenGen]

We have the same problem buddy

[@iforgotilikebikes8543]

I hope you solved it by now!

[@KuyaGenGen]

@@iforgotilikebikes8543 the thing is Incompatible chain and cog

[@rosscopantani4678]

Wtf did I just watch

[@iforgotilikebikes8543]

Even I can't believe how many people watched this by now. lol. I even looked up a few chain slipping vids before but sorta noticed no one had a crappy old odoro head cam to tape onto the pole, so I did! haha. Thanks for watching even if you got nothing out of it.