Shimano 105 R7000 - chain rub on new bike

kevin.marman

Hi folks,

I finally bit the bullet and bought a new road bike: a Canyon Endurace 7, alloy frame, Shimano 105 groupset (52/36 chainset, 11/34 cassette), disc brakes. It's a lovely bit of kit, and quite a step up from my previous Specialized Sequoia (much as I love that old bike!)

I managed to get everything set up and have been enjoying getting used to it. I've got one little niggle, though, which so far - and in spite of several efforts - I've been unable to eliminate. I'm getting a very slight, but noticeable chain rub on three cogs when I'm on the large chainwheel. Counting inwards on the cassette, it's cogs 4, 5 and 6. That's it. Just those three. Nothing else at all on any of the others, on both chainwheels.

I know the design on these new front derailleurs is different now. I found an excellent article online describing their finer details - the shifter trims, cable adjuster screw, and the new 'toggle style' working of the High and Low screws. It also laid out a method for fine-tuning to eliminate chain rub as much as possible. I've followed this to the letter. But after having the bike up on the stand several times for micro-adjustments, I've still not been able to eliminate the rub when in those 3 gears on the large ring. I can understand it not being present the higher I go, as there's less angle on the chain. But I would have though that it would be more noticeable as I change down to the larger cogs. No, though... clean on those. It's just the three mentioned.

Does anyone have any suggestions, please, about what could be causing it? Adjusting the cable tension doesn't seem to do anything. I'm inclined to think it can only be an adjustment to those High/Low screws. But nothing I try seems to make any difference.

It's a brazed-on mounting, by the way, and the height seems right based on the little sticker that was on the derailleur plate. I had been thinking about trying to adjust that just slightly to see if it worked. But I thought I'd ask here first if there's something else I could try.

Thanks for any suggestions anyone may have.

trevor.hall12

Is the small grub screw that is used for the angle butted to the frame while in the small ring and its parallel to the chainring
Often it's the angle that causes this

Could also be the half click down before doing the cable tension grub screw to line up the lines

kevin.marman

Thanks. I've got the lines lined up okay. Not so sure about the angle issue you mention. I'll check.

kevin.marman

trevor.hall12 said:

Is the small grub screw that is used for the angle butted to the frame while in the small ring and its parallel to the chainring
Often it's the angle that causes this

Could also be the half click down before doing the cable tension grub screw to line up the lines

I think that might have done it! Thank you. The article I mentioned did detail the adjustment you mentioned on the grub screw - but from what I could see at the time, it was touching the frame plate. However, I gave it a couple of turns and could see that it wasn't quite touching. After that, I noticed the rub had shifted up a couple of cogs, almost up to top gear. A small adjustment to the High Limit screw then seemed to get rid of that. It now seems to be running smoothly in all the gears. I'll check it out tomorrow on a run, though. It was annoying me because I had the Specialized set up without any chain rub at all. That had a Claris 3-wheel chainset with a Tiagra rear derailleur. Old system, though. Thanks again for your time and help.

seanoconn

This video helped me get the set up right when I was having issues with my new Canyon Endurance. It’s worth sticking it back on the stand and following every step. Any kind of chain rub spoils my enjoyment and you don’t need to put up with it.

https://youtu.be/8SO54cdwtxc

trevor.hall12

kevin.marman said:

trevor.hall12 said:

Is the small grub screw that is used for the angle butted to the frame while in the small ring and its parallel to the chainring
Often it's the angle that causes this

Could also be the half click down before doing the cable tension grub screw to line up the lines

I think that might have done it! Thank you. The article I mentioned did detail the adjustment you mentioned on the grub screw - but from what I could see at the time, it was touching the frame plate. However, I gave it a couple of turns and could see that it wasn't quite touching. After that, I noticed the rub had shifted up a couple of cogs, almost up to top gear. A small adjustment to the High Limit screw then seemed to get rid of that. It now seems to be running smoothly in all the gears. I'll check it out tomorrow on a run, though. It was annoying me because I had the Specialized set up without any chain rub at all. That had a Claris 3-wheel chainset with a Tiagra rear derailleur. Old system, though. Thanks again for your time and help.

Glad you got it sorted

kevin.marman

@trevor.hall12 Okay... I'm going to sound like a complete novice here - but I am on a bike with this spec! I had a good test run this morning - and the chain rub was still there on those same three cogs. What I discovered, though, was that if I changed the trimming on those gears, the rub stopped. Having re-read the article afterwards, I realise that I hadn't read it properly! I thought that when changing between the chainwheels, it was always necessary to give one click on the small lever after the change to get the correct trim. I now realise that the position (High or High Trim) depends on the size of the rear sprockets. It's just getting used to the new set-up. On my Specialized, with 3 chainwheels and an 8 sprocket cassette, I always had clean changing with no need to trim at all. So... it was down to incorrect operation (and inexperience and/or lack of attention to detail!) rather than anything else. Thanks, anyway. Some lessons learned!

kevin.marman

seanoconn said:

This video helped me get the set up right when I was having issues with my new Canyon Endurance. It’s worth sticking it back on the stand and following every step. Any kind of chain rub spoils my enjoyment and you don’t need to put up with it.

https://youtu.be/8SO54cdwtxc

Thanks for that! As you'll see from my latest comment - it was really due to my not reading instructions properly about trimming! I didn't have the problem on my old bike, so it's been about getting used to the new spec. That video is very useful. Here's the link to the article I mentioned, if it's any help: https://cycling-obsession.com/modern-shimano-front-derailleur-adjustment-guide/

kevin.marman

Hi all. I thought I should just come back and add a bit to the story. In spite of all my efforts, the chain rub persisted in the same gears as mentioned - even if at a very low level. However, I have hearing hypersensitivity, and could still pick it up. And it was driving me nuts - especially as on my other bike I have a triple chainset and get no chainrub at all - even in cross-chain positions. I contacted Canyon, who advised me to take the bike to my local cycle shop and get them to try to fix the issue, and they would cover my costs. So I did, today. The guy there noticed the problem straight away. The large chain ring is buckled. Not by much. Less than a millimetre. But that was the cause of the problem. Canyon have now agreed to cover the cost of a replacement large chain ring, including labour. I can't imagine how a component as strong as a large chain ring could have been damaged in transit - but there it is. It always pays to check.

seanoconn

Glad you got it sorted in the end Kevin. Damaged in transit perhaps? You’re lucky to get the bike at all if with UPS.