Skipping chain and dumbfounded

hsiaolc
hsiaolc Posts: 492
edited July 2016 in Workshop
Recently I replaced my chain. At first I used KMC 11 gold chain and measured exactly the same link with the original shimano 11 speed chain. Put it on and it skips at every turn and keeps dropping off the crank.

Then I swapped it with Shimano 11s chain and it works perfectly.

I am dumbfounded because KMC clearly states it works with all 11 speed drive train and I can't believe the difference is so huge that it make it skip?

Anyone has any ideas why KMC is skipping on my 11 Speed Di2 ultegra drive?

Comments

  • webboo
    webboo Posts: 6,087
    Worn cassette
  • keef66
    keef66 Posts: 13,123
    Is the Shimano chain the original or a new one?
  • hsiaolc
    hsiaolc Posts: 492
    keef66 wrote:
    Is the Shimano chain the original or a new one?

    New one and works flawlessly.
  • hsiaolc
    hsiaolc Posts: 492
    Webboo wrote:
    Worn cassette

    If the new shimano chain also skips but it doesn't and is working flawlessly and doesn't skip at all.

    If new Shimano chain also skips then it is either my cassette and crank.
  • redvision
    redvision Posts: 2,958
    Some chains are directional. Check to see if the kmc chain was. Would possibly explain it.

    Alternatively, was it definitely routed through the rear mech correctly? If not it could throw the chain off.
  • keef66
    keef66 Posts: 13,123
    No, me neither. I'm as puzzled as you then...
  • fenix
    fenix Posts: 5,437
    Stiff link when you reassembled ?
  • dee4life2005
    dee4life2005 Posts: 773
    A slight twist in one of the links in the KMC chain maybe? -I know it's new, but it could have been damaged in transit either to you or where you bought it from (its a long shot though). If it's not directional I'd be having a closer look. Does it look normal when you lay it out fully on a bench / table?
  • milemuncher1
    milemuncher1 Posts: 1,472
    The last two Ultegra chains I have bought have been directional, I put one on upside down / back to front, and it skipped a bit, I put it on correctly ( and made sure I had no stiff links) and it stopped skipping. I also found that the indexing was a bit of a mare, until I tightened / tensioned the cable to the rear mech a tiny bit.
  • hsiaolc
    hsiaolc Posts: 492
    redvision wrote:
    Some chains are directional. Check to see if the kmc chain was. Would possibly explain it.

    Alternatively, was it definitely routed through the rear mech correctly? If not it could throw the chain off.

    Shimano are directional but KMCs are not.

    Yes it was routed correctly.
  • hsiaolc
    hsiaolc Posts: 492
    A slight twist in one of the links in the KMC chain maybe? -I know it's new, but it could have been damaged in transit either to you or where you bought it from (its a long shot though). If it's not directional I'd be having a closer look. Does it look normal when you lay it out fully on a bench / table?

    It looks bling and new.
  • hsiaolc
    hsiaolc Posts: 492
    The last two Ultegra chains I have bought have been directional, I put one on upside down / back to front, and it skipped a bit, I put it on correctly ( and made sure I had no stiff links) and it stopped skipping. I also found that the indexing was a bit of a mare, until I tightened / tensioned the cable to the rear mech a tiny bit.

    DI2 so no rear mech tension problem. (DI2 is amazingly accurate).

    I tried both ways with the chain and it skips at every turn and actually it falls off both the large or the small crack set.
  • cycleclinic
    cycleclinic Posts: 6,865
    There are many reasons why it could be. All we can do here is guess. a mechanic maybe you maybe one from a shop has to look critically at the chain you have installed.

    Had a skipping issue with a fresh chain on a moulton that turned out to be the b tension screw but this was skipping at the cassette end.

    Maybe there is a bent chainring tooth causing it drop. there is insufficent info in the post to know why this is happening. take it to a shop to sort if you cant that what LBS are for.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • DeVlaeminck
    DeVlaeminck Posts: 8,746
    It must be the chain surely if another new chain works perfectly ?

    So either the chain is not compatible with your groupset in some way, it's been installed wrongly (directional or the joining link is the wrong way up - that can make a chain skip) or it is damaged which you should be able to see by locating the bit that skips.

    OK so you say it is compatible and it isn't directional - so I'd go for either joining link upside down or installed incorrectly somehow or else damaged link.
    [Castle Donington Ladies FC - going up in '22]
  • hsiaolc
    hsiaolc Posts: 492
    It must be the chain surely if another new chain works perfectly ?

    So either the chain is not compatible with your groupset in some way, it's been installed wrongly (directional or the joining link is the wrong way up - that can make a chain skip) or it is damaged which you should be able to see by locating the bit that skips.

    OK so you say it is compatible and it isn't directional - so I'd go for either joining link upside down or installed incorrectly somehow or else damaged link.

    It can only be the chain I guess especially with the new shimano chain it is working flawlessly (well I have to adjust the RD just a a tiny notch to be perfect.

    But just gutted I can't use the KMC gold especially I was looking forward to use the master link so I can finally do some deep cleaning on the chain.
  • hsiaolc
    hsiaolc Posts: 492
    Fenix wrote:
    Stiff link when you reassembled ?

    KMC master link so no stiff link.