New Chain Problems

Hi there, I need some help here with my chain/drivetrain.

I will try my best to explain in great detail, I also have videos filmed to show exactly what I mean.

I was doing some maintenance on my MTB before the season start and I decided to change my chain to a new one since the old one was ca 2 years old and looked worn.

I took off my old one and compared the links so I have the exact amount on the new one.
While comparing I noticed that the old one was slightly longer than the new one (no problem because chains lengthen as they wear)

Now to the problem:
If I squeeze the brake and try to pedal the chain lifts out of the grooves in the chainring. Same thing happens if I sit on the bike and start pedaling it sounds wierd and its feels not smooth. Here is the video showing exactly what i mean:
https://youtu.be/Pf-OKO1e89g

If I shift to the larger chainring the problem disappears. Check this video on the 2nd chainring, chain is barely moving at all:
https://youtu.be/Q8TkpHn01Bs

Hope someone can help me with this
Thank you
«1

Comments

  • whyamihere
    whyamihere Posts: 7,713
    Those chainrings look pretty worn, and the movement backs that up. Time to replace them I'm afraid. You'll also want to check the cassette unless that's been replaced as well.
  • steve_sordy
    steve_sordy Posts: 2,452
    Something I learned on this forum:
    "You can't teach new chains to old cogs"

    In other words, old chains and cogs (front rings as well as cassettes) wear into each other and run OK even when old. But fit a new chain and all hell breaks out! The solution is to re-fit your old chain until you can buy a new cassette and possibly new rings. But do it quickly.

    Worn gears can be identified, but it needs some experience of having seen worn ones before; just looking for "sharkfins" is not good enough.
  • webboo
    webboo Posts: 6,087
    Of course you can fit a new chain to an old cassette. You have change your chain before it’s too worn. I get at least 4 chains to a cassette on my road bike.
  • webboo said:

    Of course you can fit a new chain to an old cassette. You have change your chain before it’s too worn. I get at least 4 chains to a cassette on my road bike.

    That’s true, and particularly important if you’re cassettes cost ( over ) a couple of hundred quid a pop. It’s all about keeping your eye on the wear, and making sure you change the chain before it’s too ‘stretched’. However ( as has been said as nauseum) if you run an overly stretched chain for any significant length of time, you will kill the cassette, and need to change chain and cassette together.
  • Something I learned on this forum:
    "You can't teach new chains to old cogs"

    Yay ;)

  • imposter2.0
    imposter2.0 Posts: 12,028

    Something I learned on this forum:
    "You can't teach new chains to old cogs"

    Except for all the times when you actually can do that. Seriously, don't listen to that guy. It's a nice catchphrase, but it's bollox.

  • gomezz
    gomezz Posts: 99

    Something I learned on this forum:
    "You can't teach new chains to old cogs"

    Except for all the times when you actually can do that. Seriously, don't listen to that guy. It's a nice catchphrase, but it's bollox.

    Strange, I have found Steve and some others on here to be very helpful .
  • imposter2.0
    imposter2.0 Posts: 12,028
    gomezz said:

    Something I learned on this forum:
    "You can't teach new chains to old cogs"

    Except for all the times when you actually can do that. Seriously, don't listen to that guy. It's a nice catchphrase, but it's bollox.

    Strange, I have found Steve and some others on here to be very helpful .
    Steve didn’t coin the phrase, the other guy did.
  • JBA
    JBA Posts: 2,852

    Something I learned on this forum:
    "You can't teach new chains to old cogs"

    Except for all the times when you actually can do that. Seriously, don't listen to that guy. It's a nice catchphrase, but it's bollox.

    You are reading out of context. The OP's chain rings and probably cassette are very worn. Fitting a new chain to them will be detrimental. So Steve's (mis)quote is true in this case.

    If you look back at some of Steve's previous posts you will see that he is very particular about swapping chains and fully understands when to do so.

    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Sonder Broken Road 2021¦ Giant Revolt Advanced 2 2019 ¦ Giant Toughtroad SLR 1 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • steve_sordy
    steve_sordy Posts: 2,452
    Hang on guys, nobody (not even the guy I got the saying from) was implying that a used cassette can never take a new chain. The key word here is "old".

    But you cannot deny that the saying is catchy and helps to explain why a new chain might not run on a cassette.

    I have never managed to get 4 consecutive chains to run on the same cassette, but that is because I ran each chain until it got to about 0.6% - 0.65% "worn" (measured by length extension). Each old chain was then discarded and the next new one fitted. That way the best I have ever achieved was 3 chains. If I tried a fourth one, the chain would not run because the cassette was just too worn. It worked OK on the workstand when under no load, but as soon as load was applied the chain would skip. The difference between the new chain and the old cassette was just too big for them to work together. Hence the saying about not being able to run new chains on old cogs. When I refitted the third chain, the cassette worked as well as it did before, not great but OK(ish). The shifting wasn't good and was starting to give problems, but refitting the third chain lasted long enough for me to find a new cassette that didn't cost the earth.

    One way to get multiple chains out of one cassette is to change chains before they get too worn. I have never fully tried it but I'm willing to venture a guess that if each chain was run to let's say 0.5% (instead of the recommended 0.75%) that I would get 4 chains.

    Another way to do as well, maybe better, and a lot more cheaply would be to just use two chains and keep swapping them at frequent intervals (let's say 0.25%). That would allow both chains to to wear into the cassette at the same rate as each other. The effect is that the cassette is never confronted with a chain that is much less worn than it is. You just keep going until the gear shifting starts misbehaving. I wonder how many miles you would get from the cassette vs the other method? I am in process of trying this approach and I'm on my second chain already, the first chain is back in its box and hung on a nail in the garage. All I have to do is to keep the bike long enough!

    Remember that the result we are looking for here is not the maximum number of chains before the cassette is worn out (an easy thing to achieve), but the maximum number of miles with least cost while the transmission is still working acceptably.
  • gethinceri
    gethinceri Posts: 1,646
    "But you cannot deny that the saying is catchy"

    I can, the saying "You can't teach new chains to old cogs" is dreadful English.
  • webboo
    webboo Posts: 6,087
    I have put a new chain on an old cassette and it jumped on the ratio I tended to use most. Avoid that gear for a few miles which isn’t that hard with 20 or 22 to choose from and the chain wears in.
  • imposter2.0
    imposter2.0 Posts: 12,028

    "But you cannot deny that the saying is catchy"

    I can, the saying "You can't teach new chains to old cogs" is dreadful English.

    As Roy Walker would say, "it's good, but it's not right"...
  • steve_sordy
    steve_sordy Posts: 2,452

    "But you cannot deny that the saying is catchy"

    I can, the saying "You can't teach new chains to old cogs" is dreadful English.

    Of course it's bad English! But who cares if it gets the point across? :)
  • LOL. There's always a way to make a sensible forum discussion descend into crap about minutiae.

    I'll be putting on a second chain before the summer and then I'll swap them about. Like Steve (and many others to be fair) says, that'll give me two chains that are equally worn into the cogs. I'm going to be keeping a good eye on the wear though as my 12-speed cassette ain't cheap to replace if I can avoid it for as long as possible.

  • imposter2.0
    imposter2.0 Posts: 12,028

    "But you cannot deny that the saying is catchy"

    I can, the saying "You can't teach new chains to old cogs" is dreadful English.

    Of course it's bad English! But who cares if it gets the point across? :)
    It doesn't though, that's the problemt. The fact is that you *can* fit a new chain to an old cassette - there are too many variables for it to be an absolute. And if a 'handy catchprase' needs that much clarification, then it's about as useful as the guy who first posted it.
  • masjer
    masjer Posts: 2,613
    A switch in time saves mine
  • masjer
    masjer Posts: 2,613
    Every cog has his day.
  • brundonbianchi
    brundonbianchi Posts: 689
    edited March 2021

    Hang on guys, nobody (not even the guy I got the saying from) was implying that a used cassette can never take a new chain. The key word here is "old".

    But you cannot deny that the saying is catchy and helps to explain why a new chain might not run on a cassette.

    I have never managed to get 4 consecutive chains to run on the same cassette, but that is because I ran each chain until it got to about 0.6% - 0.65% "worn" (measured by length extension). Each old chain was then discarded and the next new one fitted. That way the best I have ever achieved was 3 chains. If I tried a fourth one, the chain would not run because the cassette was just too worn. It worked OK on the workstand when under no load, but as soon as load was applied the chain would skip. The difference between the new chain and the old cassette was just too big for them to work together. Hence the saying about not being able to run new chains on old cogs. When I refitted the third chain, the cassette worked as well as it did before, not great but OK(ish). The shifting wasn't good and was starting to give problems, but refitting the third chain lasted long enough for me to find a new cassette that didn't cost the earth.

    One way to get multiple chains out of one cassette is to change chains before they get too worn. I have never fully tried it but I'm willing to venture a guess that if each chain was run to let's say 0.5% (instead of the recommended 0.75%) that I would get 4 chains.

    Another way to do as well, maybe better, and a lot more cheaply would be to just use two chains and keep swapping them at frequent intervals (let's say 0.25%). That would allow both chains to to wear into the cassette at the same rate as each other. The effect is that the cassette is never confronted with a chain that is much less worn than it is. You just keep going until the gear shifting starts misbehaving. I wonder how many miles you would get from the cassette vs the other method? I am in process of trying this approach and I'm on my second chain already, the first chain is back in its box and hung on a nail in the garage. All I have to do is to keep the bike long enough!

    Remember that the result we are looking for here is not the maximum number of chains before the cassette is worn out (an easy thing to achieve), but the maximum number of miles with least cost while the transmission is still working acceptably.

    It’s actually very dependent on the conditions you do the miles in as well. If you do all the miles in really poor conditions, with a gash quality lube, you’re going to get more issues, more quickly than someone doing the miles in ideal conditions, and keeping everything cleaned and lubed. Get a chain checker, replace before you hit 1% ‘stretch’ and as long as you keep everything maintained, there’s no reason you shouldn’t get through more than a couple of chains, and the mileage that goes with that, before you need to change cassette. However, if you fail to maintain everything, and let the chain go over 1% ‘stretch’ for any significant mileage, you’ll almost certainly kill the cassette, and then the adage holds , “You can’t teach an old cog new links” ( it’s a play on the phrase / words ‘you can’t teach an old dog new tricks’.
  • masjer said:

    A switch in time saves mine

    That’s pretty good.
  • brundonbianchi
    brundonbianchi Posts: 689
    edited March 2021
    webboo said:

    I have put a new chain on an old cassette and it jumped on the ratio I tended to use most. Avoid that gear for a few miles which isn’t that hard with 20 or 22 to choose from and the chain wears in.

    Not all cassettes are created equal. Some cassettes ( or individual sprockets ) are more resilient than others. Ergo, you could get away with it, but that’s certainly not ‘best practice’, and the risk of the resultant top tube in the nuts when the chain slips isn’t worth the risk I.M.E.
  • webboo
    webboo Posts: 6,087
    edited March 2021
    Not only could I get away with it, I have. Also not all of us are new to the game and have to make it up.
  • imposter2.0
    imposter2.0 Posts: 12,028

    webboo said:

    I have put a new chain on an old cassette and it jumped on the ratio I tended to use most. Avoid that gear for a few miles which isn’t that hard with 20 or 22 to choose from and the chain wears in.

    Not all cassettes are created equal. Some cassettes ( or individual sprockets ) are more resilient than others. Ergo, you could get away with it, but that’s certainly not ‘best practice’, and the risk of the resultant top tube in the nuts when the chain slips isn’t worth the risk I.M.E.
    You don't really know what you're talking about, do you...
  • webboo said:

    Not only could I get away with it, I have. Also not all of us are new to the game and have to make it up.

    That’s funny, you seem exactly that to me.
  • anim4l
    anim4l Posts: 18
    *update*

    Thanks all for answering this thread and also helping.

    I managed to replace both chainrings and that made a big difference. The things you see in the video are now resolved.

    1 issue still remains.

    I feel the chain skipping on some gears when pedaling hard. Gear 8/9/1/4 work great without skipping. What could be the solution to this problem?

    Here is a picture of my casette. Does it look worn to you?




    Thanks
  • paulwood
    paulwood Posts: 231
    I get 3-4 chains per cassette and then 3-4 cassettes per outer chainring. Inner chainring seems to last for ages. I don't think there is a shortcut for having to change then when they need it.
  • anim4l
    anim4l Posts: 18
    Ok so what about the skipping gears problem? Worn casette or something else?
  • whyamihere
    whyamihere Posts: 7,713
    Yes, some of the gaps look elongated which suggests worn teeth. With how worn the chainrings were, it's not surprising that the cassette is worn too.
  • steve_sordy
    steve_sordy Posts: 2,452
    The trough between the teeth are almost flat bottomed in places. That shows a lot of wear. The new chain will not engage with the correct number of teeth and will skip.

    Fit a new cassette.
  • anim4l
    anim4l Posts: 18

    Yes, some of the gaps look elongated which suggests worn teeth. With how worn the chainrings were, it's not surprising that the cassette is worn too.

    The trough between the teeth are almost flat bottomed in places. That shows a lot of wear. The new chain will not engage with the correct number of teeth and will skip.

    Fit a new cassette.

    Thank you! I will fit a new cassette!