Ultegra R8000 front derailleur chain rub

sbbefc
sbbefc Posts: 189
Hello,

Just wondering if anyone can help. I recently acquired a new bike and in the smallest three sprockets the chain rubs against the front derailleur. Not a huge issue but it annoys me. I've adjusted the tension to the point where there is a very small gap between the crank arm and the derailleur but it still rubs. If I adjust it any more the crank arm would rub against the derailleur. Is there anything that can be done? Or will I just have to live with it?
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Comments

  • singleton
    singleton Posts: 2,523
    The front mech has 4 positions:
    Big ring trim and untrim
    Small ring trim and untrim
    I have the same mech and with the trim you can get the full range on the rear cassette without chain rub.
  • trevor.hall12
    trevor.hall12 Posts: 451
    edited October 2022
    The 8000 has a specific way to be set up using the markers on the FD if they are aligned and set up properly it's shouldn't rub .
  • First.Aspect
    First.Aspect Posts: 16,011
    Is it aligned correctly? Outer frame should be aligned with the outer face of the chain ring.
  • sbbefc
    sbbefc Posts: 189
    singleton said:

    The front mech has 4 positions:
    Big ring trim and untrim
    Small ring trim and untrim
    I have the same mech and with the trim you can get the full range on the rear cassette without chain rub.

    Unfortunately trimming the big ring only gets rid of chain rub when using the lower gears. When untrimmed its still rubbing using the higher gears.
  • singleton
    singleton Posts: 2,523
    sbbefc said:

    singleton said:

    The front mech has 4 positions:
    Big ring trim and untrim
    Small ring trim and untrim
    I have the same mech and with the trim you can get the full range on the rear cassette without chain rub.

    Unfortunately trimming the big ring only gets rid of chain rub when using the lower gears. When untrimmed its still rubbing using the higher gears.
    Okay - your initial post didn't say which ring you were in when getting the rubbing.
    Sounds like the mech needs to be adjusted to be further out, then trimming will bring it back in a bit for the lower gears.
  • seanoconn
    seanoconn Posts: 11,516
    https://youtu.be/8SO54cdwtxc
    https://youtu.be/9zZWAUp6oOE

    Found these useful when I messed up my front mech. Might not all apply but will help you check your derailleur is set up correctly. R700 is the same set up as R800
    Pinno, מלך אידיוט וחרא מכונאי
  • sbbefc
    sbbefc Posts: 189
    singleton said:

    sbbefc said:

    singleton said:

    The front mech has 4 positions:
    Big ring trim and untrim
    Small ring trim and untrim
    I have the same mech and with the trim you can get the full range on the rear cassette without chain rub.

    Unfortunately trimming the big ring only gets rid of chain rub when using the lower gears. When untrimmed its still rubbing using the higher gears.
    Okay - your initial post didn't say which ring you were in when getting the rubbing.
    Sounds like the mech needs to be adjusted to be further out, then trimming will bring it back in a bit for the lower gears.
    Thanks for your responses. The trouble is, the mech is as far out as I can get it. There's only a small slither of a gap between its outer edge and the crank arm. The mech itself is attached to a bracket on the frame so all I can do to adjust it is move it up and down. I've moved it down a touch so there's a gap of 1/2mm. Will give it a try later.
  • seanoconn
    seanoconn Posts: 11,516
    edited October 2022
    sbbefc said:

    singleton said:

    sbbefc said:

    singleton said:

    The front mech has 4 positions:
    Big ring trim and untrim
    Small ring trim and untrim
    I have the same mech and with the trim you can get the full range on the rear cassette without chain rub.

    Unfortunately trimming the big ring only gets rid of chain rub when using the lower gears. When untrimmed its still rubbing using the higher gears.
    Okay - your initial post didn't say which ring you were in when getting the rubbing.
    Sounds like the mech needs to be adjusted to be further out, then trimming will bring it back in a bit for the lower gears.
    Thanks for your responses. The trouble is, the mech is as far out as I can get it. There's only a small slither of a gap between its outer edge and the crank arm. The mech itself is attached to a bracket on the frame so all I can do to adjust it is move it up and down. I've moved it down a touch so there's a gap of 1/2mm. Will give it a try later.
    Tightening the mech cable will move the cage out further on the big ring.
    But the cage shouldn’t be close to the crank arm. Post some pics if you get the chance.
    Pinno, מלך אידיוט וחרא מכונאי
  • First.Aspect
    First.Aspect Posts: 16,011
    C h e c k a l i g n m e n t

    At least rule that out, because its the only adjustment you have left. Sometimes chain rub is caused by the rear of the cage being angled slightly to the non drive side.

    It's the only mech adjustment you have left, assuming you've done the obvious thing and checked that it is indeed at the end stop when it is rubbing.
  • MattFalle
    MattFalle Posts: 11,644
    you've set up the cable into the mech correctly, yah? cable run and grub screw?
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • sbbefc said:

    singleton said:

    sbbefc said:

    singleton said:

    The front mech has 4 positions:
    Big ring trim and untrim
    Small ring trim and untrim
    I have the same mech and with the trim you can get the full range on the rear cassette without chain rub.

    Unfortunately trimming the big ring only gets rid of chain rub when using the lower gears. When untrimmed its still rubbing using the higher gears.
    Okay - your initial post didn't say which ring you were in when getting the rubbing.
    Sounds like the mech needs to be adjusted to be further out, then trimming will bring it back in a bit for the lower gears.
    Thanks for your responses. The trouble is, the mech is as far out as I can get it. There's only a small slither of a gap between its outer edge and the crank arm. The mech itself is attached to a bracket on the frame so all I can do to adjust it is move it up and down. I've moved it down a touch so there's a gap of 1/2mm. Will give it a try later.
    I don't think you have it set up properly ,the video above will get you where you need to be
  • MattFalle
    MattFalle Posts: 11,644
    correct cable routing in piccies - remrmber to use grub screw correctly




    .
    The camera down the willy isn't anything like as bad as it sounds.
  • wongataa
    wongataa Posts: 1,001
    Download the Shimano installation instructions from the Shimano website. Take the cable off the derailleur. Set the derailleur up from scratch following the instructions to the letter. Now when using the appropriate trim positions you won't get any rub.
  • sbbefc
    sbbefc Posts: 189
    Thanks for the responses. I'm going to have to start again. The bike is brand new so I thought it would have been set up ready to go without this faff.

    The chain also rubs (quite a bit more) on the inside of the derailleur when in the smallest chain ring and in my lowest gear too. I've slacked it all off and screwed the lower limit screw and to the point it doesn't go any further. I have no choice but undo the cable and start again.
  • lesfirth
    lesfirth Posts: 1,382
    I am tempted to say " I have the same problem" except it is not a problem because I never use little sprockets with my small chainring. There is no need to, you have very similar gear ratios in big chainring and 2/3 bigger sprockets ( i.e. cogs on your cassette). Using bigger chainrings and sprockets is more efficient. Probably not enough for me to notice but Ganna used 65 +14 on his 1 hour record ride. He could have used 51+11 for the same ratio but he did not for a reason.
    OP, just stop watching videos , ride your bike and smell the flowers.
  • MattFalle
    MattFalle Posts: 11,644
    if its brand new just take it back to the shop and get them to sort it.
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • andyrr
    andyrr Posts: 1,822
    MattFalle said:

    if its brand new just take it back to the shop and get them to sort it.

    …hope it wasn’t bought at Halfords as it might not be part of their PDI …
  • sbbefc
    sbbefc Posts: 189
    lesfirth said:

    I am tempted to say " I have the same problem" except it is not a problem because I never use little sprockets with my small chainring. There is no need to, you have very similar gear ratios in big chainring and 2/3 bigger sprockets ( i.e. cogs on your cassette). Using bigger chainrings and sprockets is more efficient. Probably not enough for me to notice but Ganna used 65 +14 on his 1 hour record ride. He could have used 51+11 for the same ratio but he did not for a reason.
    OP, just stop watching videos , ride your bike and smell the flowers.

    It's my lowest gear. The biggest sprocket with the smallest chainring.
  • sbbefc
    sbbefc Posts: 189
    MattFalle said:

    if its brand new just take it back to the shop and get them to sort it.

    Unfortunately it's some distance from where I live.
  • MattFalle
    MattFalle Posts: 11,644
    edited October 2022
    sbbefc said:

    MattFalle said:

    if its brand new just take it back to the shop and get them to sort it.

    Unfortunately it's some distance from where I live.
    how far?

    alternatively, take to a different shop?
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • MattFalle
    MattFalle Posts: 11,644
    edited October 2022
    andyrr said:

    MattFalle said:

    if its brand new just take it back to the shop and get them to sort it.

    …hope it wasn’t bought at Halfords as it might not be part of their PDI …
    seems that no matter where it was bought it wasn't part of their pdi tbh fam innit
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • photonic69
    photonic69 Posts: 2,622
    edited October 2022
    Photos will help to sort your issues. Pics of chainring and derailleur side on and end on with chain on big ring and small sprocket.


    Sometimes. Maybe. Possibly.

  • MattFalle said:

    if its brand new just take it back to the shop and get them to sort it.

    This is what I would do or if distance is an issue talk to them about getting itvto the nearest dealer at their expense.
    Only issue might be if they actually built it ,which would be quite rare .
  • MattFalle
    MattFalle Posts: 11,644
    but but but but shouldn't they have checked it as part of their pdi before letting it out of the shop??????
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • MattFalle said:

    andyrr said:

    MattFalle said:

    if its brand new just take it back to the shop and get them to sort it.

    …hope it wasn’t bought at Halfords as it might not be part of their PDI …
    seems that no matter where it was bought it wasn't part of their pdi tbh fam innit
    I recently had a Liv in 3 weeks old .
    Major retailer
    62 year old asked for it to be geared for hills
    She got 52/36 ,11/30
    A power meter she didn't ask for and on inspection after 2 visits to fix the gears not working properly the customer came to me it was clear on inspection whoever set it up didn't have a clue how to do the 8000 series FD .
    Of all the shimano stuff the 7000/8000 seems to be where most set up issues happen

  • photonic69
    photonic69 Posts: 2,622
    MattFalle said:

    but but but but shouldn't they have checked it as part of their pdi before letting it out of the shop??????

    We've no way of telling what happened to the bike after it left the shop. He might have inadvertently knocked the front derailleur loading/unloading from car for instance. What the shop did is by the by. What the OP needs is clear advice on how to fix it himself. We need photos of what is happening to advise him correctly.


    Sometimes. Maybe. Possibly.

  • First.Aspect
    First.Aspect Posts: 16,011
    As he seems able to change gear okay, this has all the hallmarks of very minor adjustment needed. There are very few things left to check. If the OP can't figure it out, he needs to take it to a bike shop. There's not much else to say.
  • MattFalle
    MattFalle Posts: 11,644
    edited October 2022
    Tbh, he's best taking it to a shop before he chews up the cable beyond hope or jeffs up the mech and/or shifter.
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • MattFalle
    MattFalle Posts: 11,644

    MattFalle said:

    andyrr said:

    MattFalle said:

    if its brand new just take it back to the shop and get them to sort it.

    …hope it wasn’t bought at Halfords as it might not be part of their PDI …
    seems that no matter where it was bought it wasn't part of their pdi tbh fam innit
    I recently had a Liv in 3 weeks old .
    Major retailer
    62 year old asked for it to be geared for hills
    She got 52/36 ,11/30
    A power meter she didn't ask for and on inspection after 2 visits to fix the gears not working properly the customer came to me it was clear on inspection whoever set it up didn't have a clue how to do the 8000 series FD .
    Of all the shimano stuff the 7000/8000 seems to be where most set up issues happen

    so what you saying?
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • edward.s
    edward.s Posts: 223
    The 7/8000 onwards setup with toggle link are often setup wrong as mentioned above - I suspect because the setup procedure is not like most other FDs. Its important to follow the Shimano setup guide.